Add auth config to germqtt

The next release of germqtt supports setting auth on the mqtt publish
commands. We don't want to configure germqtt to send authorized events.
This commit adds the fields to configure germqtt to handle this.

Change-Id: I24a0cdb6a41f6e440db8e68216b19ca61b4cba31

manifests/server.pp

@@ -24,6 +24,8 @@ class germqtt::server (
   $mqtt_hostname = 'firehose01.openstack.org',
   $topic = 'gerrit',
   $pid_file = '/var/run/germqtt.pid',
+  $mqtt_username = 'infra',
+  $mqtt_password,
 ) {
   file { '/etc/germqtt.conf':
     ensure  => present,

templates/germqtt.conf.erb

@@ -9,3 +9,5 @@ key = <%= @gerrit_key %>
 [mqtt]
 hostname = <%= @mqtt_hostname %>
 topic = <%= @topic %>
+username = <%= @mqtt_username %>
+password = <%= @mqtt_password %>