Build slack-integration plugin on stable-3.3

Change-Id: I862f921ee631a1953964fdfec539c6e1411c1176
diff --git a/jenkins/gerrit-bazel-plugin-slack-integration.yaml b/jenkins/gerrit-bazel-plugin-slack-integration.yaml
index 505ba14..8d0de59 100644
--- a/jenkins/gerrit-bazel-plugin-slack-integration.yaml
+++ b/jenkins/gerrit-bazel-plugin-slack-integration.yaml
@@ -1,14 +1,11 @@
 - project:
     name: slack-integration
     jobs:
-      - 'plugin-{name}-bazel-{branch}-{gerrit-branch}':
-          branch:
-            - master
-          gerrit-branch:
-            - master
-            - stable-3.2
       - 'plugin-{name}-bazel-{branch}':
           branch:
+            - master
+            - stable-3.3
+            - stable-3.2
             - stable-3.1
             - stable-3.0
             - stable-2.16