Revert "Switch to PyPy nightly"

[illia-v]

This reverts #3434 (closes #3433) because PyPy v7.3.23 was released.

https://pypy.org/posts/2026/05/pypy-v7322-release.html

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00000%. Comparing base (d66c4fb) to head (879b88f).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@               Coverage Diff               @@
##                 main        #3447   +/-   ##
===============================================
  Coverage   100.00000%   100.00000%           
===============================================
  Files             128          128           
  Lines           19419        19417    -2     
  Branches         1317         1317           
===============================================
- Hits            19419        19417    -2     

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[illia-v]

Hmm, the PyPy job failed.

I opened this PR after seeing this fixed for urllib3, this means that without check-latest: true actions/setup-python still installs the previous version of PyPy.

[A5rocks]

Interesting, I didn't know about that configuration! I think we should enable that.