Don't pull event from DB when handling replication traffic. (#8669)

I was trying to make it so that we didn't have to start a background task when handling RDATA, but that is a bigger job (due to all the code in `generic_worker`). However I still think not pulling the event from the DB may help reduce some DB usage due to replication, even if most workers will simply go and pull that event from the DB later anyway.

Co-authored-by: Patrick Cloke <clokep@users.noreply.github.com>