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: ✅ SUCCESS

Descriptor	Linter	Files	Fixed	Errors	Elapsed time
✅ PYTHON	black	32		0	0.95s
✅ PYTHON	pylint	32		0	6.13s

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.87%. Comparing base (32fbf15) to head (178a465).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #378   +/-   ##
=======================================
  Coverage   97.86%   97.87%           
=======================================
  Files          27       27           
  Lines        1544     1550    +6     
=======================================
+ Hits         1511     1517    +6     
  Misses         33       33           

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]

Suggested change

	"formula": None,
	"formula": test_config.get("formula"),

Just in case the user has specified a formula in the test config.

[jmafoster1]

Suggested change

	else {"error": result.error_message}
	else {"status": "error", "reason": result.error_message}

I quite liked the status/reason format. It might even be nice to include it as part of the "normal" output as well, e.g. "status": "passed/failed". Then we can just query test["result"]["status"]

[jmafoster1]

Would it be sensible to move the commonalities between the if and the else into a single entry and then update the bits that differ in order to make the code a bit DRY-er? Less to maintain in the future...