Convert fileformats/nc_load_rules to pytest

[ESadek-MO]

🚀 Pull Request

Description

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• benchmark_this Request that this pull request be benchmarked to check if it introduces performance shifts

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.18%. Comparing base (aebae6d) to head (72516b8).
⚠️ Report is 62 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #6896   +/-   ##
=======================================
  Coverage   90.18%   90.18%           
=======================================
  Files          91       91           
  Lines       24822    24822           
  Branches     4656     4656           
=======================================
  Hits        22385    22385           
  Misses       1669     1669           
  Partials      768      768           

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[HGWright]

Just one thing to change in a few places, from the ruff check --select PT then this is good to go.

[HGWright]

Thanks @ESadek-MO