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/ironic/conductor/storage/cinder.yml b/ironic/conductor/storage/cinder.yml
index 33af09a..22dc687 100644
--- a/ironic/conductor/storage/cinder.yml
+++ b/ironic/conductor/storage/cinder.yml
@@ -11,5 +11,5 @@
         project_domain_id: default
         project_name: service
         user_domain_name: Default
-        username: cinder
+        username: ${_param:keystone_cinder_username}
         region: ${_param:openstack_region}