fix(CI): Run on latest ubuntu

[tvdeyen]

We need latest libvips for latest Rails

Summary

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.07%. Comparing base (72f9fcd) to head (2faf745).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #6531   +/-   ##
=======================================
  Coverage   95.07%   95.07%           
=======================================
  Files         460      460           
  Lines        7924     7924           
=======================================
  Hits         7534     7534           
  Misses        390      390           

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[mamhoff]

I think this has been superseded by #6532