This container can be pulled via:
  docker pull registry.opensuse.org/isv/suse/edge/3.4/images/3.4/frr:8.5.6
  docker pull registry.opensuse.org/isv/suse/edge/3.4/images/3.4/frr:8.5.6-7.2

Set DOCKER_CONTENT_TRUST=1 to enable image tag verification.