rework: use vitest instead of jest ⚡

[jamacku]

• also update dependencies
• remove jest related files

[codecov]

Codecov Report

Attention: Patch coverage is 70.27027% with 11 lines in your changes missing coverage. Please review.

Project coverage is 83.88%. Comparing base (c0957f2) to head (b0d015a).
Report is 14 commits behind head on main.

Files with missing lines	Patch %	Lines
itest/bugzilla-environment.ts	60.71%	11 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #155      +/-   ##
==========================================
- Coverage   87.66%   83.88%   -3.79%     
==========================================
  Files           5        8       +3     
  Lines         300      844     +544     
  Branches       56      128      +72     
==========================================
+ Hits          263      708     +445     
- Misses         37      134      +97     
- Partials        0        2       +2     

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