This container can be pulled via:
  docker pull registry.opensuse.org/isv/rancher/elemental/dev/containers/suse/sl-micro/6.1/kvm-iso-image:2.3.0-dev
  docker pull registry.opensuse.org/isv/rancher/elemental/dev/containers/suse/sl-micro/6.1/kvm-iso-image:2.3.0-dev-204.16
  docker pull registry.opensuse.org/isv/rancher/elemental/dev/containers/suse/sl-micro/6.1/kvm-iso-image:latest

Set DOCKER_CONTENT_TRUST=1 to enable image tag verification.