Fix token parsing error

Change-Id: Ic16ddba4018978e01fb5f6301ccb28477b9970a4
diff --git a/ceilometer/server/cluster.yml b/ceilometer/server/cluster.yml
index 2b2030c..b5d8013 100644
--- a/ceilometer/server/cluster.yml
+++ b/ceilometer/server/cluster.yml
@@ -8,7 +8,7 @@
     server:
       enabled: true
       version: ${_param:ceilometer_version}
-      region: ${_param: openstack_region}
+      region: ${_param:openstack_region}
       cluster: true
       secret: ${_param:ceilometer_secret_key}
       ttl: 86400