Add periodic task to clear schedule of queries whose schedule until value is in the past

[arikfr]

We now have an optional expiry date for the query schedule. We should add a periodic Celery task to clear the schedule on such queries.

[aidarbek]

Does it really have to be a separate task? I just saw this line

redash/redash/models/__init__.py

Line 572 in af168c6

if schedule_until <= now:

Which is executed when refresh_queries celery task is running. Maybe adding schedule clearing inside of this if statement could solve this issue?

[arikfr]

That's an option too. I wouldn't do the update in-place though, but rather return the list of queries to remove scheduling of from outdated_queries call, and then do the schedule removal after doing the queries refresh.