Move composer-require-checker to CI installation

[Firehed]

This should avoid conflicts with the php-parser in updated package and platform versions.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 81.33%. Comparing base (b00dfd9) to head (40da29e).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##               main      #93   +/-   ##
=========================================
  Coverage     81.33%   81.33%           
  Complexity      311      311           
=========================================
  Files            33       33           
  Lines          1034     1034           
=========================================
  Hits            841      841           
  Misses          193      193           

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