Bugfix: Added support for '.' in pkg_name for python_requires_extend

[LBHawk]

Closes #7241

Changelog: (Bugfix): Added support for '.' in pkg_name for python_requires_extend

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[memsharded]

Hi @LBHawk

The test that is failing in CI is unrelated, don't worry about it, it is already fixed.

Please:

• Add a red-green test for this new behavior, to guarantee no future regressions
• Please sign the CLA above, check if you did the commit with the same Github user

Many thanks for contributing this fix!

[memsharded]

This was implemented and fixed in #7262
Thanks for your contribution!