Refactor Prowler parser to address feedback

- Removed test_mode parameter and related functionality, making the parser cleaner and more maintainable
- Changed file detection to prioritize extensions first before content inspection
- Added notes content directly to finding description instead of using separate notes fields
- Removed all database operations (.save() calls)
- Fixed handling of test files to ensure all test cases pass successfully
- Added proper tag handling for all cloud providers in both file-based and StringIO-based tests
- Ensured consistent severity and active status handling across all providers and formats

Author: cosmel-dojo