🧹 refactor(test): consolidate testdataPath helper

[jackby03]

🎯 What: Consolidates duplicated testdataPath helper functions found in test files (auditd, logging, containers) into a shared internal/modules/util/testutil package.
💡 Why: Reduces duplicate code, making the codebase easier to maintain. Provides a standard way to get test data paths.
✅ Verification: Ran make test and all tests passed.
✨ Result: Improved maintainability and reduced duplicate logic in test files.

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PR created automatically by Jules for task 18202564033375836344 started by @jackby03

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