Note that we (cross) compile for both arm64 and the universal2.
This may feel redundant, it can still be interesting to have both.
While universal2 is more convenient arm64 is lighter.

Also drop Python 3.7 (end-of-life 2023-06-27).
Add Python 3.12 and pypy-3.10 support.

Bump CI actions versions as well.

It seems like we can't use env in stragegy.matrix, refs:
- https://github.com/orgs/community/discussions/56787
- #54 (comment)