chore: Delete MultiverseTesting tool and associated workflow

[tippmar-nr]

MultiverseTesting is dead. Long live MultiverseTesting! ☠️

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 82.21%. Comparing base (8c70ed2) to head (c293459).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3057      +/-   ##
==========================================
+ Coverage   82.18%   82.21%   +0.03%     
==========================================
  Files         477      477              
  Lines       30623    30623              
  Branches     3426     3426              
==========================================
+ Hits        25166    25177      +11     
+ Misses       4658     4646      -12     
- Partials      799      800       +1     

Flag	Coverage Δ
Agent	83.27% <ø> (+0.03%)	⬆️
Profiler	72.51% <ø> (ø)

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see 3 files with indirect coverage changes

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