test: Add DST Fall Back cases for CronExpression behavior
Adds two test cases to verify that `CronExpression` correctly handles
ambiguous local times during the end of Daylight Saving Time (Fall Back).
These tests ensure accurate computation of:
- the previous fire time (used to name archived log files)
- the next fire time (used to determine the rollover instant)
Correct handling is critical to avoid overwriting log files when:
- rotation occurs twice on the same local day, or
- the same filename is generated due to repeated local times (even across different calendar days).
2 files changed
