fix 0020-sources-for-python-packaging.rst source distribution URL

Fixes #2

rfcs/0020-sources-for-python-packaging.rst

@@ -58,5 +58,5 @@ Alternatives Considered
 We may continue using sdist tarballs from `PyPI`_, that did not provide signature files. However, this does not provide a clear policy for packagers and increases their workload in cases where the sdist tarballs are broken.
 
 .. _PyPI: https://pypi.org
-.. _source distribution: https://docs.python.org/3/distutils/sourcedist.html
+.. _source distribution: https://docs.python.org/3.11/distutils/sourcedist.html
 .. _setuptools#3672: https://github.com/pypa/setuptools/issues/3672