Generate random keystone users

Depends-On: https://gerrit.mcp.mirantis.com/#/c/44319/
Depends-On: https://gerrit.mcp.mirantis.com/#/c/45118/
Depends-On: https://gerrit.mcp.mirantis.com/#/c/45119/

Related-Prod: PROD-29868
Related-Prod: PROD-31315
(cherry picked from commit f5956c2f6151cc5d99659103f90641ea66eac44a)
(cherry picked from commit 70dd0f0587eb297fbefdea43837839c4983b8378)

Change-Id: I402be73437d5397224184a4fd71e2f6abae24db2
diff --git a/barbican/server/single.yml b/barbican/server/single.yml
index c1ef15e..1ee95f7 100644
--- a/barbican/server/single.yml
+++ b/barbican/server/single.yml
@@ -9,6 +9,8 @@
   barbican:
     server:
       database:
+        user: ${_param:mysql_barbican_username}
+        password: ${_param:mysql_barbican_password}
         x509:
           enabled: ${_param:openstack_mysql_x509_enabled}
           ca_file: ${_param:mysql_barbican_ssl_ca_file}
@@ -18,6 +20,8 @@
           enabled: ${_param:galera_ssl_enabled}
       role: ${_param:openstack_node_role}
       identity:
+        user: ${_param:keystone_barbican_username}
+        password: ${_param:keystone_barbican_password}
         protocol: ${_param:internal_protocol}
       message_queue:
         port: ${_param:openstack_rabbitmq_port}