Fixes causal test results misalignment when skip:true tests are present

[f-allian]

• In causal_testing/main.py, the save_results method now filters out tests marked with "skip": true in the test configuration, so only active tests are paired with their results and saved.

• In tests/main_tests/test_main.py, both test_ctf and test_ctf_exception_silent now use only active tests (not skipped) when checking which tests passed, aligning the test logic with the updated main code.

• Closes issue Misaligned test results when skip:true tests are present in causal tests #377

[github-actions]

🦙 MegaLinter status: ⚠️ WARNING

Descriptor	Linter	Files	Fixed	Errors	Elapsed time
⚠️ PYTHON	black	32		1	1.2s
✅ PYTHON	pylint	32		0	6.06s

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.87%. Comparing base (2fac254) to head (e262f67).
⚠️ Report is 9 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #378      +/-   ##
==========================================
+ Coverage   97.29%   97.87%   +0.57%     
==========================================
  Files          27       27              
  Lines        1555     1551       -4     
==========================================
+ Hits         1513     1518       +5     
+ Misses         42       33       -9     

Files with missing lines	Coverage Δ
causal_testing/main.py	100.00% <100.00%> (ø)

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[jmafoster1]

This solution means that skipped tests don't make it into the results file. Personally, I'd prefer they were still there so we have a record of all the test outcomes so we know if any where skipped (as opposed to not generated/considered). It'd be good to preserve order too if we can, although putting skipped test cases at the end is more acceptable than not having them there at all.

[f-allian]

@jmafoster1

Is this what you're after? For example, a causal test case with skip:true:

    {
      "name": "treatment --> outcome",
      "estimator": "LinearRegressionEstimator",
      "estimate_type": "coefficient",
      "effect": "direct",
      "treatment_variable": "treatment",
      "formula": "treatment ~ outcome",
      "alpha": 0.05,
      "skip": true,
      "expected_effect": {
        "treatment": "SomeEffect"
      }
}

now has a corresponding result:

  {
    "name": "treatment --> outcome",
    "estimate_type": "coefficient",
    "effect": "direct",
    "treatment_variable": "treatment",
    "expected_effect": {
      "treatment": "SomeEffect"
    },
    "formula": null,
    "alpha": 0.05,
    "skip": true,
    "passed": null,
    "result": {
      "status": "skipped",
      "reason": "Test marked as skip:true in the causal test config file.
    }
}  

[jmafoster1]

This is a nice solution. I've suggested a couple of potential minor improvements

[jmafoster1]

Thanks @f-allian. This looks good to me