Remove unneeded `skip_doctest` decorator usages

IPython/core/debugger.py

@@ -114,7 +114,6 b' from IPython import get_ipython'
 from IPython.utils import PyColorize
 from IPython.utils import coloransi, py3compat
 from IPython.core.excolors import exception_colors
-from IPython.testing.skipdoctest import skip_doctest
 
 # skip module docstests
 __skip_doctest__ = True
@@ -180,7 +179,6 b' class Tracer(object):'
     while functioning acceptably (though with limitations) if outside of it.
     """
 
-    @skip_doctest
     def __init__(self, colors=None):
         """
         DEPRECATED
@@ -921,7 +919,6 b' class Pdb(OldPdb):'
                 return True
         return False
 
-    @skip_doctest
     def _is_in_decorator_internal_and_should_skip(self, frame):
         """
         Utility to tell us whether we are in a decorator internal and should stop.

IPython/core/magics/execution.py

@@ -413,7 +413,6 b' class ExecutionMagics(Magics):'
         self.shell.call_pdb = new_pdb
         print('Automatic pdb calling has been turned',on_off(new_pdb))
 
-    @skip_doctest
     @magic_arguments.magic_arguments()
     @magic_arguments.argument('--breakpoint', '-b', metavar='FILE:LINE',
         help="""

IPython/core/magics/osm.py

@@ -63,7 +63,6 b' class OSMagics(Magics):'
         super().__init__(shell=shell, **kwargs)
 
 
-    @skip_doctest
     def _isexec_POSIX(self, file):
         """
             Test for executable on a POSIX system
@@ -75,14 +74,12 b' class OSMagics(Magics):'
 
 
     
-    @skip_doctest
     def _isexec_WIN(self, file):
         """
             Test for executable file on non POSIX system
         """
         return file.is_file() and self.execre.match(file.name) is not None
 
-    @skip_doctest
     def isexec(self, file):
         """
             Test for executable file on non POSIX system