This container can be pulled via:
  docker pull registry.opensuse.org/isv/rancher/elemental/maintenance/6.0/containers/suse/sl-micro/6.0/rt-iso-image:2.1.3
  docker pull registry.opensuse.org/isv/rancher/elemental/maintenance/6.0/containers/suse/sl-micro/6.0/rt-iso-image:2.1.3-1.13
  docker pull registry.opensuse.org/isv/rancher/elemental/maintenance/6.0/containers/suse/sl-micro/6.0/rt-iso-image:latest

Set DOCKER_CONTENT_TRUST=1 to enable image tag verification.