Use bazelisk for gerrit and plugins builds

Bazelisk allows to automatically switch between bazel versions
using the .bazelversion file on the Gerrit home folder.

Change-Id: Ie1bdae2a2f350e900cb666b8e5b8d0ee42c15a4a
16 files changed
tree: 00b5693431463b1c93fab96f1fa6b6702a19fcd9
  1. jenkins/
  2. jenkins-docker/
  3. worker/
  4. .gitignore