Add Python 3.12 support, drop Python 3.7 support

[gi0baro]

Changes summary

• Add Python 3.12 support
• Drop Python 3.7 support
• Bump PyO3 to 0.20
• Add pypy3.10 wheels in CI

[codecov]

Codecov Report

Merging #248 (b3fd20f) into main (eb0df3a) will not change coverage.
The diff coverage is n/a.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #248   +/-   ##
=======================================
  Coverage   99.51%   99.51%           
=======================================
  Files           6        6           
  Lines         416      416           
  Branches       82       82           
=======================================
  Hits          414      414           
  Misses          1        1           
  Partials        1        1           

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[gi0baro]

@samuelcolvin I'm not sure why the failing test on linux (seems flaky?)..

Regarding everything else let me know your comments/objections :)

[samuelcolvin]

looks good to me, but I would say, given it's the same test failing every time, that there is something wrong.

[gi0baro]

@samuelcolvin yeah, the strange thing to me is that is passing only on stable rust and py 3.11.
Gonna experiment with this a bit locally, I'll update you.

[gi0baro]

@samuelcolvin probably it was the scanning of / taking too much time. I changed the test, see b3fd20f

[samuelcolvin]

Awesome, thank you.

I'll do a release today.