This container can be pulled via:
  docker pull registry.opensuse.org/isv/rancher/elemental/dev/containers_next/rancher/elemental-teal-rt-channel:1.4.0
  docker pull registry.opensuse.org/isv/rancher/elemental/dev/containers_next/rancher/elemental-teal-rt-channel:1.4.0-7.18
  docker pull registry.opensuse.org/isv/rancher/elemental/dev/containers_next/rancher/elemental-teal-rt-channel:latest

Set DOCKER_CONTENT_TRUST=1 to enable image tag verification.