Add alerting for RadosGW Usage Exporter metrics

Author: MoteHue

etc/kayobe/kolla/config/prometheus/ceph.rules

@@ -1,8 +1,7 @@
 # Modified official set of upstream alerts https://github.com/ceph/ceph/blob/octopus/monitoring/prometheus/alerts/ceph_default_alerts.yml
 
-{% raw %}
-
 groups:
+{% raw %}
 - name: health
   rules:
   - alert: HealthError
@@ -205,7 +204,6 @@ groups:
       description: "{{ $value }} OSD requests are taking too long to process (osd_op_complaint_time exceeded)"
 
 {% endraw %}
-
 {% if stackhpc_enable_radosgw_usage_exporter | bool %}
 - name: rgws
   rules: