fix: use python=3.12,3.13 in the CI tests

[ycexiao]

What problem does this PR address?

Closes #12

What should the reviewer(s) do?

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.94%. Comparing base (a06f7f0) to head (e9d5974).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #14      +/-   ##
==========================================
+ Coverage   92.46%   92.94%   +0.48%     
==========================================
  Files           4        4              
  Lines         146      156      +10     
==========================================
+ Hits          135      145      +10     
  Misses         11       11              

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[ycexiao]

@sbillinge, it's ready for review.