Fix test configs and utils

[toinehartman]

• Remove import of test configs from main Checker module.
• Fix inconsistencies in test path configs.
• Re-use code in testing utils.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 46%. Comparing base (3e0ccc6) to head (45d8fc6).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##              main   #2712   +/-   ##
=======================================
  Coverage       46%     46%           
- Complexity    6679    6680    +1     
=======================================
  Files          795     795           
  Lines        65905   65905           
  Branches      9881    9881           
=======================================
+ Hits         30716   30722    +6     
- Misses       32804   32805    +1     
+ Partials      2385    2378    -7     

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[toinehartman]

@PaulKlint This PR is mostly intended to remove the test code from the checker at runtime. I'll launch an integration test to make sure this does not introduce any unwanted side effects.

[toinehartman]

Test run: https://github.com/usethesource/rascal-core-big-tests/actions/runs/23139373095 https://github.com/usethesource/rascal-core-big-tests/actions/runs/23155127223

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud