Changing apache_horizon_api_address

the patch changes parameter to be relay on horizon
server structure and parameter horizon_server_bind_address.

Change-Id: I8961ffba3ee37fabdaba120507cb49c1bc28f768
Related-PROD: PROD-25528
diff --git a/apache/server/site/horizon.yml b/apache/server/site/horizon.yml
index 2a3b098..4cf7820 100644
--- a/apache/server/site/horizon.yml
+++ b/apache/server/site/horizon.yml
@@ -3,7 +3,7 @@
     apache_ssl:
       enabled: false
     apache_horizon_ssl: ${_param:apache_ssl}
-    apache_horizon_api_address: ${_param:single_address}
+    apache_horizon_api_address: ${_param:horizon_server_bind_address}
     apache_horizon_api_host: ${linux:network:fqdn}
   apache:
     server: