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/mysql/client/database/ironic.yml b/mysql/client/database/ironic.yml
index e142e64..9441f74 100644
--- a/mysql/client/database/ironic.yml
+++ b/mysql/client/database/ironic.yml
@@ -7,11 +7,11 @@
             ironic:
               encoding: utf8
               users:
-              - name: ironic
+              - name: ${_param:mysql_ironic_username}
                 password: ${_param:mysql_ironic_password}
                 host: '%'
                 rights: all
-              - name: ironic
+              - name: ${_param:mysql_ironic_username}
                 password: ${_param:mysql_ironic_password}
                 host: ${_param:cluster_local_address}
                 rights: all