Build login-redirect plugin on stable-3.4 branch

Change-Id: Ib15f7f19c96291fd4445e43e3f78ac890714354a
diff --git a/jenkins/gerrit-bazel-plugin-login-redirect.yaml b/jenkins/gerrit-bazel-plugin-login-redirect.yaml
index 3c83477..ecd8351 100644
--- a/jenkins/gerrit-bazel-plugin-login-redirect.yaml
+++ b/jenkins/gerrit-bazel-plugin-login-redirect.yaml
@@ -6,6 +6,7 @@
             - master
           gerrit-branch:
             - master
+            - stable-3.4
             - stable-3.3
             - stable-3.2
             - stable-3.1