add defaults for cicd
diff --git a/docker/swarm/service/gerrit.yml b/docker/swarm/service/gerrit.yml
index d1bdfae..d33bdbb 100644
--- a/docker/swarm/service/gerrit.yml
+++ b/docker/swarm/service/gerrit.yml
@@ -1,4 +1,6 @@
 parameters:
+  _param:
+    docker_image_gerrit: tcpcloud/gerrit:2.12.7
   docker:
     client:
       service: