This container can be pulled via:
  docker pull registry.opensuse.org/devel/kubic/containers/container/kubic/etcd:3.5.21
  docker pull registry.opensuse.org/devel/kubic/containers/container/kubic/etcd:3.5.21-0
  docker pull registry.opensuse.org/devel/kubic/containers/container/kubic/etcd:3.5.21-0.14.367
  docker pull registry.opensuse.org/devel/kubic/containers/container/kubic/etcd:3.5.21-1
  docker pull registry.opensuse.org/devel/kubic/containers/container/kubic/etcd:3.5.21-1.14.367

Set DOCKER_CONTENT_TRUST=1 to enable image tag verification.