Update event.py (Birthday Bug)

This should fix the Birthday Bug.
What I did:
You still need the if (e.starts_on and e.ends_on) else date
this checks if it has starts on date and ends on date
If it doesn't have those dates it will use the main date.

Filter
if date >= start and date <= end and date <= repeat:
I added more values on the if statement.
IF the date is LESS THAN or EQUAL to END DATE, it will add the event.