Optimized activity clean-up query

[martastain]

Refactored activity clean-up query, that caused timeouts in the clean-up process. Now it should not.

Testing

• BACKUP!!!!!!
• Start ayon
• Wait a couple of minutes
• Validate that activities of existing entities weren't deleted

More testing

clean-up does not touch activities that were updated or their parent entities were deleted in last 10 days.

You may therefore:

• Find an entity with 10 days or older comment
• Delete that entity
• Delete related entity.xxxxx.deleted event from the events table
• Restart the server and wait a couple of minutes
• In the server log, you should see Deleted {count} orphaned activities from {project_name}