The API already promises this, the comment on effective_replication_map says:
"Excludes replicas which are in the left state".
Tablet replicas on the replaced node are rebuilt after the node
already left. We may no longer have the IP mapping for the left node
so we should not include that node in the replica set. Otherwise,
storage_proxy may try to use the empty IP and fail:
storage_proxy - No mapping for :: in the passed effective replication map
It's fine to not include it, because storage proxy uses keyspace RF
and not replica list size to determine quorum. The node is not coming
up, so noone should need to contact it.
Users which need replica list stability should use the host_id-based API.
Fixes#18843
(cherry picked from commit 0d596a425c)
7479167af2