Remove deprecated nats.tls.hostname property

This property used to be used to set the hostname to connect
to NATS over mTLS. We now get that from the nats-tls link and
this property is already no longer used.

Author: Michael Mokrysz

jobs/route_registrar/spec

@@ -53,8 +53,6 @@ properties:
     description: "PEM-encoded certificate for the route-emitter to present to NATS for verification when connecting via TLS."
   nats.tls.client_key:
     description: "PEM-encoded private key for the route-emitter to present to NATS for verification when connecting via TLS."
-  nats.tls.hostname:
-    description: "Hostname of the NATS cluster."
 
   host:
     description: (string, optional) By default, route_registrar will detect the IP of the VM and use it, in combination with port as the backend destination for each uri being registered. This property enables overriding the destination hostname or IP.