[DO NOT MERGE] Migrate xdist to use logical cores instead of only physical

[mlxd]

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Context: Xdist will only use 2 of the 4 virtual cores on a Github actions runner due to it polling physical cores. This PR switches -n auto to -n logical allowing use of the logical cores. Do not merge unless performance increases.

Description of the Change: As above.

Benefits:

Possible Drawbacks:

Related GitHub Issues:

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.34%. Comparing base (1011e55) to head (3c9dca8).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3199      +/-   ##
==========================================
+ Coverage   95.32%   95.34%   +0.01%     
==========================================
  Files         177      177              
  Lines       20874    20874              
  Branches     2103     2103              
==========================================
+ Hits        19899    19903       +4     
+ Misses        768      764       -4     
  Partials      207      207              

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