Fixed gerrit triggering in mirror jobs

Change-Id: Ia340e33a827c64c66791bfb1614eca3d309a693e
diff --git a/jenkins/client/job/git-mirrors/2way.yml b/jenkins/client/job/git-mirrors/2way.yml
index 330abc2..15f78d7 100644
--- a/jenkins/client/job/git-mirrors/2way.yml
+++ b/jenkins/client/job/git-mirrors/2way.yml
@@ -36,6 +36,9 @@
                   "{{source}}":
                     branches:
                       - master
+                event:
+                  ref:
+                    - updated
             param:
               SOURCE_URL:
                 type: string