Replace openstack_proxy_address with cluster_public_host

In addition to template changes https://gerrit.mcp.mirantis.com/29621

Change-Id: I1d469d46e4931dec809c3f74ebbb3a98dfdc06a1
Closes-bug: PROD-24645 (PROD-25495)
diff --git a/murano/server/cluster.yml b/murano/server/cluster.yml
index 6c45f6d..a9b1f6d 100644
--- a/murano/server/cluster.yml
+++ b/murano/server/cluster.yml
@@ -40,7 +40,7 @@
         virtual_host: '/openstack'
       murano_agent_queue:
         engine: rabbitmq
-        host: ${_param:openstack_proxy_address}
+        host: ${_param:cluster_public_host}
         port: 5673
         user: openstack
         password: ${_param:rabbitmq_murano_agent_password}