Support older Python versions (3.7+)

[llucax]

What's needed?

We received a couple of requests for adding support for older versions of Python for projects using repo-config, but they are blocked because this repo still needs 3.11+.

Proposed solution

Make this repo compatible with older Python versions, if possible 3.7+.

Use cases

• Allow pymdownx-superfence-filter-lines-python to work with python 3.7-3.11 pymdownx-superfence-filter-lines-python#24
• Add Python 3.10 support setuptools-betterproto#15

Alternatives and workarounds

No response

Additional context

No response