`event_push_actions_staging` can have many stale rows in them.

[matrixbot]

This issue has been migrated from #14029.

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This is mostly likely due to previous bugs, or due to restarts.

matrix-org/synapse#14020 adds a background job to clear them out.

Once that has worked through the current stale rows we should check if we still see stale rows added, and if so investigate where they are coming from.