Silence warnings for NDPermuter file

[mlxd]

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Context: This silences the warnings issued from codefactor for the NDPermuter class.

Description of the Change: As above.

Benefits: Prevents false warnings in other PRs

Possible Drawbacks: May miss opportunity for improvements to this class.

Related GitHub Issues:

[github-actions]

Hello. You may have forgotten to update the changelog!
Please edit .github/CHANGELOG.md with:

• A one-to-two sentence description of the change. You may include a small working example for new features.
• A link back to this PR.
• Your name (or GitHub username) in the contributors section.

[multiphaseCFD]

Thanks @mlxd !

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 98.51%. Comparing base (6ca460a) to head (0240cda).
Report is 83 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #750      +/-   ##
==========================================
+ Coverage   97.99%   98.51%   +0.52%     
==========================================
  Files          90      102      +12     
  Lines       13701    14861    +1160     
  Branches      336        0     -336     
==========================================
+ Hits        13426    14640    +1214     
+ Misses        275      221      -54     

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