Don't use subunit user on logstash workers

The logstash workers don't have a subunit user so don't use it to set
file ownership. Instead just set file ownership to root as the file just
needs to be readable by the logstash worker processes.

Change-Id: I14a4fbf879d64b883bceb1bb227bb8b392f654ba

modules/openstack_project/manifests/logstash_worker.pp

@@ -66,8 +66,8 @@ class openstack_project::logstash_worker (
       ensure  => present,
       content => $mqtt_ca_cert_contents,
       replace => true,
-      owner   => 'subunit',
-      group   => 'subunit',
+      owner   => 'root',
+      group   => 'root',
       mode    => '0555',
   }