Add stable-3.2 to slave-bazel cache warmup

Change-Id: I6be73fb42cf3039a6cbd718aaba1a36b8120563b
diff --git a/jenkins-docker/slave-bazel/Dockerfile b/jenkins-docker/slave-bazel/Dockerfile
index 6ca857e..fa38ef9 100644
--- a/jenkins-docker/slave-bazel/Dockerfile
+++ b/jenkins-docker/slave-bazel/Dockerfile
@@ -14,6 +14,9 @@
     git checkout -f stable-3.1 && \
     git submodule update --init && \
     ( bazelisk build --remote_cache=https://gerrit-ci.gerritforge.com/cache --noremote_upload_local_results plugins:core release api || true ) && \
+    git checkout -f stable-3.2 && \
+    git submodule update --init && \
+    ( bazelisk build --remote_cache=https://gerrit-ci.gerritforge.com/cache --noremote_upload_local_results plugins:core release api || true ) && \
     git checkout -f master && \
     git submodule update --init && \
     ( bazelisk build --remote_cache=https://gerrit-ci.gerritforge.com/cache --noremote_upload_local_results plugins:core release api || true ) && \