tests(feat[test_log]): Add comprehensive tests for vcspull logging utilities

why: Ensure proper testing coverage for all logging formatters and setup functionality
what:
- Add test_log.py with comprehensive test coverage for all log components
- Test LogFormatter, DebugLogFormatter, SimpleLogFormatter, RepoLogFormatter classes
- Test RepoFilter functionality and setup_logger behavior
- Test integration scenarios with actual loggers
- Follow vcspull testing patterns with NamedTuple parametrized tests
- Include proper pytest fixtures for logger cleanup

Author: tony