CI: simplify tests execution

[shenanigansd]

Testing out removing some of the layers in this command execution.

[codspeed-hq]

Merging this PR will not alter performance

✅ 2 untouched benchmarks

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_{Comparing shenanigansd-patch-1 (478e808) with main (504a72b)}

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.29%. Comparing base (504a72b) to head (478e808).
⚠️ Report is 1 commits behind head on main.
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #149   +/-   ##
=======================================
  Coverage   88.29%   88.29%           
=======================================
  Files           3        3           
  Lines          94       94           
=======================================
  Hits           83       83           
  Misses         11       11           

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[Copilot]

Pull request overview

Simplifies the Python CI test invocation by reducing the number of layers used to run coverage/pytest under uv.

Changes:

• Updates the CI test step command to call coverage and pytest more directly via uv run.

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[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.

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