Mark bulk cron workers as idempotent
Description
This marks bulk cron workers as idempotent. This was done before !123620 (merged), but we reverted after some issues !135817 (merged). Now we can try to enable them again #341385 (comment 2157362681).
This mostly reverts the changes from !135817 (merged).
Related to #341375 (closed) and #341385 (closed).