Cluster redirecting to admin port

[andydunstall]

Once a migration is finished in Dragonfly, but not yet finalized by the control plane (with cluster config), Dragonfly redirects to the internal IP and admin port, not the configured public domain and port

Such as we should redirect to eq0e9hvo2-qoixobx8a.dragonflydb.cloud:6379, but instead redirect to 10.5.34.191:9999

This means clients can't follow the redirect, both because it needs the domain not the IP (for TLS verification), and it needs the public port not the admin port