Build go-import plugin on stable-3.4 branch

Change-Id: If00cde501482834aff4763a922fac0e5ae02780f
diff --git a/jenkins/gerrit-bazel-plugin-go-import.yaml b/jenkins/gerrit-bazel-plugin-go-import.yaml
index 3154956..3b3617b 100644
--- a/jenkins/gerrit-bazel-plugin-go-import.yaml
+++ b/jenkins/gerrit-bazel-plugin-go-import.yaml
@@ -8,6 +8,7 @@
             - master
       - 'plugin-{name}-bazel-{branch}':
           branch:
+            - stable-3.4
             - stable-3.3
             - stable-3.2
             - stable-2.16