Comment 5 for bug 1724353

Turns out there was another bug about this issue, and it was fixed in bionic:

docker.io (17.03.2-0ubuntu2) bionic; urgency=medium
  * Replace "--no-restart-on-upgrade" with "--no-start" and a debconf prompt
    - not restarting Docker causes many issues (LP: #1658691)
    - suggested methods for keeping containers up are to use a restart policy
      ("--restart=..." on "docker run"), Swarm Mode services, or rolling
      replacement of k8s workers
  * Backport 30519 for bashism (LP: #1744599)

Xenial and Artful are still affected.