Generate random keystone users

Change-Id: I8dbd07b10d29b43d1c35fa76bcaa0f0efb32beda
Related-Prod: PROD-29868
diff --git a/murano/server/single.yml b/murano/server/single.yml
index 8c85019..1512893 100644
--- a/murano/server/single.yml
+++ b/murano/server/single.yml
@@ -17,14 +17,14 @@
         host: ${_param:openstack_database_address}
         port: 3306
         name: murano
-        user: murano
+        user: ${_param:mysql_murano_username}
         password: ${_param:mysql_murano_password}
       identity:
         engine: keystone
         host: ${_param:openstack_control_address}
         port: 35357
         tenant: service
-        user: murano
+        user: ${_param:keystone_murano_username}
         password: ${_param:keystone_murano_password}
       message_queue:
         engine: rabbitmq