Generate random keystone users

Change-Id: I8dbd07b10d29b43d1c35fa76bcaa0f0efb32beda
Related-Prod: PROD-29868
diff --git a/gnocchi/common/cluster.yml b/gnocchi/common/cluster.yml
index b00ffa5..e1c58da 100644
--- a/gnocchi/common/cluster.yml
+++ b/gnocchi/common/cluster.yml
@@ -6,6 +6,8 @@
   gnocchi:
     common:
       database:
+        user: ${_param:mysql_gnocchi_username}
+        password: ${_param:mysql_gnocchi_password}
         x509:
           enabled: ${_param:openstack_mysql_x509_enabled}
           ca_file: ${_param:mysql_gnocchi_ssl_ca_file}