Require apt-get update before installing extra packages

When running the Docker build in cache mode, the update
phase may not be executed and the extra packages setup would fail.

Include an extra apt-get update to make sure that the Docker
image can be built in both cache and non-cache modes.

Change-Id: Ie67063349871e33bf830682da282079b7ddfa75b
1 file changed
tree: 514dfc86b4e43034c81086069cef3e18d706f476
  1. jenkins/
  2. jenkins-docker/
  3. worker/
  4. .gitignore