Replacing APT repo

[syphernl]

The currently used apt repository (apt.dockerproject.org) seems to have old packages dating back from the 2017. As a result, support for Ubuntu 18.04 (Bionic) is missing.

According to the official docs, there is a different repository. It's probably a good idea to switch to this one instead.

For now I've been able to make it work with this:

extend:
  docker package repository:
    pkgrepo.managed:
      - name: deb [arch=amd64] https://download.docker.com/linux/ubuntu {{ salt['grains.get']('oscodename') }} stable
      - key_url: https://download.docker.com/linux/ubuntu/gpg
      - keyid: 0EBFCD88
  docker package:
    pkg.installed:
      - name: docker-ce

[aboe76]

@syphernl can you make a PR?

[javierbertoli]

Fixed on #151