Turn off pip caching in workflows to fix disk space issue

[rwedge]

Resolves #511

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 76.71%. Comparing base (c4b9eba) to head (c15d4dd).
⚠️ Report is 5 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #512   +/-   ##
=======================================
  Coverage   76.71%   76.71%           
=======================================
  Files          30       30           
  Lines        2456     2456           
=======================================
  Hits         1884     1884           
  Misses        572      572           

Flag	Coverage Δ
integration	62.47% <ø> (ø)
unit	70.27% <ø> (ø)

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