revert temporary workaround on centos

https://review.openstack.org/#/c/288244/ has been merged so RabbitMQ
should not steal Keystone UID / GID anymore.

Change-Id: Iebc6ec2a9a3a3a7adb3949d9a91992056422356f

manifests/init.pp

@@ -6,8 +6,5 @@ class openstack_integration {
     package { 'openstack-selinux':
         ensure => 'latest'
     }
-    # temporary hack to make sure RabbitMQ does not steal UID
-    # of Keystone
-    Package<| title == 'keystone' |> -> Package<| title == 'rabbitmq-server' |>
   }
 }