Clear out device_lists_changes_in_room table periodically.

[erikjohnston]

We added the device_lists_changes_in_room table in #12321, we should clear it out periodically so that it doesn't grow indefinitely.

Note that we want to use this new table in e.g. /sync #12388, so we need to make sure we correctly handle that case.

[florian-sabonchi]

Hello I would like to take a look. Someone else working on it? @erikjohnston What do you think about clearing the table in sync function, this is called in regular intervals.

[richvdh]

It would be great to make this happen. device_lists_changes_in_room and its associated indexes are now taking up 3.2G of my 30G database.

[dklimpel]

Is there a workaround, some SQL statement or anything else, to clean up this table?

EDIT:
some solution #12821 (comment) ?

Open question