Starting on boot and setting `replicaof` should be able to be configured independently for Redis

Followup to https://gitlab.com/gitlab-com/gl-infra/chef-repo/-/merge_requests/2707#note_1232269487 we should have two explicit configuration options to prevent the scenario we had in gitlab-com/gl-infra/production#8201 (closed) where redis didn't start after reboot.

We currently have the ha: true set which prevents redis starting on boot, but also prevents replicaof in the config which is needed (originally added in !2651 (merged)).

I'm marking this priority1 severity1 because the corresponding incident was severity1