Cleanup yum/dnf cache after repositories setup

... to ensure the latest packages are pulled from these repos.

Change-Id: If40c3cb012bced4d825714a84024354bece53b75

manifests/repo/redhat/redhat.pp

@@ -178,6 +178,7 @@ class openstack_extras::repo::redhat::redhat(
     file { $filename:
       path   => "/etc/yum.repos.d/${filename}",
       source => $url,
+      notify => Exec['yum_refresh'],
     }
   }