Comment From: wilkinsona
I couldn't get this to work, even with the tasks marked as privileged, so I've reverted the changes for now. To allow the staging builds to run, I've also reverted 51d57e1. It was an unsuccessful attempt to work around some rate limiting problems and is what meant that the build required Docker to be running.
It would still be good to get this working on CI so that staging builds can run all the Docker-based tests.
Comment From: wilkinsona
I'm not sure that this really matters and there are benefits, namely speed, to not running the Docker-based tests during staging.