Require pygments>=2.4.0

As noted in  #13441, running ipython with an old version of pygments
leads to problems. Ipython sends ANSI color names to pygments to color
output, but these names aren't in old versions of pygments.

Before: with pygments 2.3.1 and ipython 8.0.0, opening an ipython
instance and running

    In [1]: 1 / 0   # Expect ZeroDivisionError

will crash ipython as `ansiyellow` is used to highlight the error.

This PR requires pygments>=2.4.0, which is when pygments changed their
ANSI color names.

setup.cfg

@@ -1,72 +1,72 b''
 [metadata]
 name = ipython
 version = attr: IPython.core.release.__version__
 url = https://ipython.org
 description = IPython: Productive Interactive Computing
 long_description_content_type = text/x-rst
 long_description = file: long_description.rst
 license_file = LICENSE
 project_urls =
     Documentation = https://ipython.readthedocs.io/
     Funding = https://numfocus.org/
     Source = https://github.com/ipython/ipython
     Tracker = https://github.com/ipython/ipython/issues
 keywords = Interactive, Interpreter, Shell, Embedding
 platforms = Linux, Mac OSX, Windows
 classifiers =
     Framework :: IPython
     Intended Audience :: Developers
     Intended Audience :: Science/Research
     License :: OSI Approved :: BSD License
     Programming Language :: Python
     Programming Language :: Python :: 3
     Programming Language :: Python :: 3 :: Only
     Topic :: System :: Shells
 
 
 [options]
 packages = find:
 python_requires = >=3.8
 zip_safe = False
 install_requires =
     setuptools>=18.5
     jedi>=0.16
     black
     decorator
     pickleshare
     traitlets>=5
     prompt_toolkit>=2.0.0,<3.1.0,!=3.0.0,!=3.0.1
-    pygments
+    pygments>=2.4.0
     backcall
     stack_data
     matplotlib-inline
     pexpect>4.3; sys_platform != "win32"
     appnope; sys_platform == "darwin"
     colorama; sys_platform == "win32"
 
 [options.packages.find]
 exclude =
     setupext
 
 [options.package_data]
 IPython.core = profile/README*
 IPython.core.tests = *.png, *.jpg, daft_extension/*.py
 IPython.lib.tests = *.wav
 IPython.testing.plugin = *.txt
 
 [options.entry_points]
 console_scripts =
     ipython = IPython:start_ipython
     ipython3 = IPython:start_ipython
 pygments.lexers =
     ipythonconsole = IPython.lib.lexers:IPythonConsoleLexer
     ipython = IPython.lib.lexers:IPythonLexer
     ipython3 = IPython.lib.lexers:IPython3Lexer
 
 [velin]
 ignore_patterns = 
    IPython/core/tests
    IPython/testing
 
 [tool.black]
 exclude = 'timing\.py'

setup.py

@@ -1,185 +1,185 b''
 # -*- coding: utf-8 -*-
 """Setup script for IPython.
 
 Under Posix environments it works like a typical setup.py script.
 Under Windows, the command sdist is not supported, since IPython
 requires utilities which are not available under Windows."""
 
 #-----------------------------------------------------------------------------
 #  Copyright (c) 2008-2011, IPython Development Team.
 #  Copyright (c) 2001-2007, Fernando Perez <[e-mail]>
 #  Copyright (c) 2001, Janko Hauser <[e-mail]>
 #  Copyright (c) 2001, Nathaniel Gray <[e-mail]>
 #
 #  Distributed under the terms of the Modified BSD License.
 #
 #  The full license is in the file COPYING.rst, distributed with this software.
 #-----------------------------------------------------------------------------
 
 import os
 import sys
 from itertools import chain
 
 # **Python version check**
 #
 # This check is also made in IPython/__init__, don't forget to update both when
 # changing Python version requirements.
 if sys.version_info < (3, 8):
     pip_message = 'This may be due to an out of date pip. Make sure you have pip >= 9.0.1.'
     try:
         import pip
         pip_version = tuple([int(x) for x in pip.__version__.split('.')[:3]])
         if pip_version < (9, 0, 1) :
             pip_message = 'Your pip version is out of date, please install pip >= 9.0.1. '\
             'pip {} detected.'.format(pip.__version__)
         else:
             # pip is new enough - it must be something else
             pip_message = ''
     except Exception:
         pass
 
 
     error = """
 IPython 8+ supports Python 3.8 and above, following NEP 29.
 When using Python 2.7, please install IPython 5.x LTS Long Term Support version.
 Python 3.3 and 3.4 were supported up to IPython 6.x.
 Python 3.5 was supported with IPython 7.0 to 7.9.
 Python 3.6 was supported with IPython up to 7.16.
 Python 3.7 was still supported with the 7.x branch.
 
 See IPython `README.rst` file for more information:
 
     https://github.com/ipython/ipython/blob/master/README.rst
 
 Python {py} detected.
 {pip}
 """.format(py=sys.version_info, pip=pip_message )
 
     print(error, file=sys.stderr)
     sys.exit(1)
 
 # At least we're on the python version we need, move on.
 
 from setuptools import setup
 
 # Our own imports
 from setupbase import target_update
 
 from setupbase import (
     setup_args,
     check_package_data_first,
     find_data_files,
     git_prebuild,
     install_symlinked,
     install_lib_symlink,
     install_scripts_for_symlink,
     unsymlink,
 )
 
 #-------------------------------------------------------------------------------
 # Handle OS specific things
 #-------------------------------------------------------------------------------
 
 if os.name in ('nt','dos'):
     os_name = 'windows'
 else:
     os_name = os.name
 
 # Under Windows, 'sdist' has not been supported.  Now that the docs build with
 # Sphinx it might work, but let's not turn it on until someone confirms that it
 # actually works.
 if os_name == 'windows' and 'sdist' in sys.argv:
     print('The sdist command is not available under Windows.  Exiting.')
     sys.exit(1)
 
 
 #-------------------------------------------------------------------------------
 # Things related to the IPython documentation
 #-------------------------------------------------------------------------------
 
 # update the manuals when building a source dist
 if len(sys.argv) >= 2 and sys.argv[1] in ('sdist','bdist_rpm'):
 
     # List of things to be updated. Each entry is a triplet of args for
     # target_update()
     to_update = [
         (
             "docs/man/ipython.1.gz",
             ["docs/man/ipython.1"],
             "cd docs/man && python -m gzip --best ipython.1",
         ),
     ]
 
 
     [ target_update(*t) for t in to_update ]
 
 #---------------------------------------------------------------------------
 # Find all the packages, package data, and data_files
 #---------------------------------------------------------------------------
 
 data_files = find_data_files()
 
 setup_args['data_files'] = data_files
 
 #---------------------------------------------------------------------------
 # custom distutils commands
 #---------------------------------------------------------------------------
 # imports here, so they are after setuptools import if there was one
 from setuptools.command.sdist import sdist
 
 setup_args['cmdclass'] = {
     'build_py': \
             check_package_data_first(git_prebuild('IPython')),
     'sdist' : git_prebuild('IPython', sdist),
     'symlink': install_symlinked,
     'install_lib_symlink': install_lib_symlink,
     'install_scripts_sym': install_scripts_for_symlink,
     'unsymlink': unsymlink,
 }
 
 
 #---------------------------------------------------------------------------
 # Handle scripts, dependencies, and setuptools specific things
 #---------------------------------------------------------------------------
 
 # setuptools requirements
 
 extras_require = dict(
     parallel=["ipyparallel"],
     qtconsole=["qtconsole"],
     doc=["Sphinx>=1.3"],
     test=[
         "pytest",
         "pytest-asyncio",
         "testpath",
-        "pygments",
+        "pygments>=2.4.0",
     ],
     test_extra=[
         "pytest",
         "testpath",
         "curio",
         "matplotlib!=3.2.0",
         "nbformat",
         "numpy>=1.19",
         "pandas",
-        "pygments",
+        "pygments>=2.4.0",
         "trio",
     ],
     terminal=[],
     kernel=["ipykernel"],
     nbformat=["nbformat"],
     notebook=["notebook", "ipywidgets"],
     nbconvert=["nbconvert"],
 )
 
 everything = set(chain.from_iterable(extras_require.values()))
 extras_require['all'] = list(sorted(everything))
 
 setup_args["extras_require"] = extras_require
 
 #---------------------------------------------------------------------------
 # Do the actual setup now
 #---------------------------------------------------------------------------
 
 if __name__ == "__main__":
     setup(**setup_args)