Fix cache warm-up in jenkins-docker/slave-buck

The slave-buck image performed the cache warm-up with the gerrit
version on master branch, which is by now using bazel to build.
Thus the build failed.

This change changes the Dockerfile to provide a working buck version
and to perform the cache warm-up using the stable-2.13 branch.

Change-Id: Ic19ae4db9b1384c51ae4cb5469c9c8eb7a5c48f0
1 file changed
tree: a0b9a4087cca644c0357fa4ef19c47ff2a2de3c3
  1. jenkins/
  2. jenkins-docker/
  3. worker/
  4. .gitignore