Add parallel testing to GitHub action phpunit

[korridor]

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 88.61%. Comparing base (48f0942) to head (7ae4f21). Report is 30 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##               main     #187   +/-   ##
=========================================
  Coverage     88.61%   88.61%           
  Complexity     1711     1711           
=========================================
  Files           264      264           
  Lines          9150     9150           
=========================================
  Hits           8108     8108           
  Misses         1042     1042           

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[CLAassistant]

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