Feature request: Run a particular job at every regular interval, except for certain ones

e.g.
```
public_holidays = [
datetime(2024, 6, 19, 0, 1, 0)
]
job = schedule.every().wednesday.at('00:01:00', 'America/Los_Angeles') \
.except(public_holidays)
```

The issue provides only a Python usage example and names no files or tests. Start by tracing the public scheduling API and existing interval execution behavior, then define how excluded dates should interact with recurring jobs; done means the example works and coverage verifies both skipped and normally scheduled runs.

Written by the indexing model from the issue text.