Build javamelody plugin on stable-3.4

Change-Id: Ib7e2b0cf495e72d9a52b43f2df6c7354fe553817
diff --git a/jenkins/gerrit-bazel-plugin-javamelody.yaml b/jenkins/gerrit-bazel-plugin-javamelody.yaml
index 2ed6539..2f66467 100644
--- a/jenkins/gerrit-bazel-plugin-javamelody.yaml
+++ b/jenkins/gerrit-bazel-plugin-javamelody.yaml
@@ -44,4 +44,5 @@
             - master
           gerrit-branch:
             - master
+            - stable-3.4
             - stable-3.3