contrib: python-hook-examples use absolute_import

contrib/python-hook-examples.py

@@ -1,7 +1,11 b''
 '''
 Examples of useful python hooks for Mercurial.
 '''
-from mercurial import patch, util
+from __future__ import absolute_import
+from mercurial import (
+    patch,
+    util,
+)
 
 def diffstat(ui, repo, **kwargs):
     '''Example usage:

tests/test-check-py3-compat.t

@@ -5,7 +5,6 b''
   $ hg files 'set:(**.py)' | sed 's|\\|/|g' | xargs python contrib/check-py3-compat.py
   contrib/import-checker.py not using absolute_import
   contrib/import-checker.py requires print_function
-  contrib/python-hook-examples.py not using absolute_import
   contrib/revsetbenchmarks.py not using absolute_import
   contrib/revsetbenchmarks.py requires print_function
   contrib/synthrepo.py not using absolute_import