Force Poetry to use correct Python version

[teutoburg]

Well, trying to run this with an unsupported version (setting the matrix to include 3.9, which the example project here doesn't support) now fails, which wasn't the case for any of my previous attempts. However, if you look carefully at the logs, it still installs with another Python environment (3.12 in this case), but then at least fails when trying to run the tests. So I'm classifying this as a partial success.

The root cause seems to be a bug in Poetry 😑

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (949fbad) to head (93b876b).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main       #60   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            2         2           
  Lines            7         7           
=========================================
  Hits             7         7           

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[hugobuddel]

Thanks! So we keep that line in to verify what version is being used?

[teutoburg]

Indeed, or rather that was the idea of the one below poetry run python -V >> "$GITHUB_STEP_SUMMARY" I recently added. That allows us to (manually) check which python, basically. But with this new one now it also actually fails when I'd expect it to. But even if that apparent bug in Poetry is fixed, I don't see any downside in keeping both lines in.