ci(mypy): redo #1480

[bearomorphism]

Description

#1466 accidentally reverted the changes in #1480. This PR is fixing that.

Checklist

• I have read the contributing guidelines

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

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Additional details and impacted files

@@             Coverage Diff              @@
##             refactors    #1509   +/-   ##
============================================
  Coverage             ?   97.82%           
============================================
  Files                ?       57           
  Lines                ?     2618           
  Branches             ?        0           
============================================
  Hits                 ?     2561           
  Misses               ?       57           
  Partials             ?        0           

Flag	Coverage Δ
unittests	97.82% <100.00%> (?)

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[bearomorphism]

Mentioned the issue in #1457 (comment)

@Lee-W I think we don't need to merge this if you can revert the force-push