gh-101100: Fix Sphinx warnings in whatsnew/2.2.rst

[hugovk]

Same rationale as #112351.

Fix 29 Sphinx warnings:

❯ SPHINXERRORHANDLING=-n PATH=./venv/bin:$PATH sphinx-build -b html -d build/doctrees -j auto -n . build/html whatsnew/2.1.rst 2>&1 | grep 2.1.rst | tee >(wc -l)
Doc/whatsnew/2.1.rst:51: WARNING: py:func reference target not found: g
Doc/whatsnew/2.1.rst:105: WARNING: py:func reference target not found: g
Doc/whatsnew/2.1.rst:162: WARNING: py:meth reference target not found: __cmp__
Doc/whatsnew/2.1.rst:182: WARNING: py:meth reference target not found: __lt__
Doc/whatsnew/2.1.rst:184: WARNING: py:meth reference target not found: __le__
Doc/whatsnew/2.1.rst:186: WARNING: py:meth reference target not found: __gt__
Doc/whatsnew/2.1.rst:188: WARNING: py:meth reference target not found: __ge__
Doc/whatsnew/2.1.rst:190: WARNING: py:meth reference target not found: __eq__
Doc/whatsnew/2.1.rst:192: WARNING: py:meth reference target not found: __ne__
Doc/whatsnew/2.1.rst:207: WARNING: py:func reference target not found: cmp
Doc/whatsnew/2.1.rst:248: WARNING: py:mod reference target not found: regex
Doc/whatsnew/2.1.rst:263: WARNING: py:mod reference target not found: regex
Doc/whatsnew/2.1.rst:275: WARNING: py:mod reference target not found: regex
Doc/whatsnew/2.1.rst:368: WARNING: py:func reference target not found: f
Doc/whatsnew/2.1.rst:382: WARNING: py:func reference target not found: memoize
Doc/whatsnew/2.1.rst:400: WARNING: py:exc reference target not found: weakref.ReferenceError
Doc/whatsnew/2.1.rst:444: WARNING: py:class reference target not found: UserDict
Doc/whatsnew/2.1.rst:586: WARNING: py:mod reference target not found: inspect.py
Doc/whatsnew/2.1.rst:586: WARNING: py:mod reference target not found: pydoc.py
Doc/whatsnew/2.1.rst:586: WARNING: py:mod reference target not found: pydoc.py
Doc/whatsnew/2.1.rst:619: WARNING: py:class reference target not found: SequenceMatcher
Doc/whatsnew/2.1.rst:631: WARNING: py:mod reference target not found: minidom
Doc/whatsnew/2.1.rst:645: WARNING: py:func reference target not found: asctime
Doc/whatsnew/2.1.rst:645: WARNING: py:func reference target not found: localtime
Doc/whatsnew/2.1.rst:725: WARNING: py:meth reference target not found: xreadlines
Doc/whatsnew/2.1.rst:725: WARNING: py:func reference target not found: xrange
Doc/whatsnew/2.1.rst:725: WARNING: py:func reference target not found: xreadlines
Doc/whatsnew/2.1.rst:725: WARNING: py:meth reference target not found: readlines
Doc/whatsnew/2.1.rst:739: WARNING: py:meth reference target not found: popitem
      29

• Issue: Fix all Sphinx reference warnings in the documentation #101100

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📚 Documentation preview 📚: https://cpython-previews--112366.org.readthedocs.build/

[miss-islington-app]

Thanks @hugovk for the PR 🌮🎉.. I'm working now to backport this PR to: 3.11, 3.12.
🐍🍒⛏🤖

[bedevere-app]

GH-114711 is a backport of this pull request to the 3.12 branch.

[bedevere-app]

GH-114712 is a backport of this pull request to the 3.11 branch.