fix: python version pinned to 3.13 in merge to main workflow

[sbillinge]

No description provided.

[github-actions]

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 50.00%. Comparing base (bfd86da) to head (9d5c36b).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #39   +/-   ##
=======================================
  Coverage   50.00%   50.00%           
=======================================
  Files           2        2           
  Lines          18       18           
=======================================
  Hits            9        9           
  Misses          9        9           

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