Revert "[3.13] pythongh-132921: Fix setuptools._distutils.dep_util deprecation (pythonGH-132923) (python#132926)"

This reverts commit 3776ade.

setuptools.modified module is not available on old setuptools
versions.

Author: vstinner

Tools/peg_generator/pegen/build.py

@@ -95,7 +95,7 @@ def compile_c_extension(
     import setuptools.logging
 
     from setuptools import Extension, Distribution
-    from setuptools.modified import newer_group
+    from setuptools._distutils.dep_util import newer_group
     from setuptools._distutils.ccompiler import new_compiler
     from setuptools._distutils.sysconfig import customize_compiler