Support for replica-announce-ip and replica-announce-port

[romange]

We host our Redis pods in K8s
When Redis replicates with a master, Redis uses the pod IP to "name" the replica
Pod IPs are ephemeral, when the pod is bounced, it comes up with a new IP
This is problematic for Redis Sentinel because as pods are bounced, it sees a new IP address for the previous replica and creates a bloated list of "dead replicas"
Redis Sentinel should not have any dead replicas, so the command sentinel reset SHARD_NAME removes them - however executing this after each pod cycle is toilsome
We mitigate this in K8s by provisioning a K8s Service with a ClusterIP
Our helm-chart has an init container which discovers the ClusterIP for the StatefulSet Pod, and sets replica-announce-ip to this value
Redis then advertises itself as being available at that IP address

[romange]

Need to see if it is possible to merge cluster_announce_ip and replica_announce_ip.
seems that they both serve the same purpose - to announce an external ip, not visible to Dragonfly process