CI: Add testing on Python 3.12, and update project metadata

[amotl]

What the title says.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (f6df18d) 97.56% compared to head (37fceeb) 97.56%.
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #21   +/-   ##
=======================================
  Coverage   97.56%   97.56%           
=======================================
  Files           3        3           
  Lines          41       41           
=======================================
  Hits           40       40           
  Misses          1        1           

Flag	Coverage Δ
unittests	97.56% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.