Add ceilometer user for ceilometer-upgrade command

Change-Id: Ia3bd9eb243f9c01a7dca0e000165d13c30fbf3e0
Related-Prod: PROD-26062
diff --git a/ceilometer/backend/upgrade.sls b/ceilometer/backend/upgrade.sls
index 31efe2c..41a52fd 100644
--- a/ceilometer/backend/upgrade.sls
+++ b/ceilometer/backend/upgrade.sls
@@ -3,6 +3,7 @@
 ceilometer_upgrade:
   cmd.run:
     - name: ceilometer-upgrade
+    - runas: 'ceilometer'
     {%- if grains.get('noservices') or server.get('role', 'primary') == 'secondary' %}
     - onlyif: /bin/false
     {%- endif %}