This container can be pulled via:
  docker pull registry.opensuse.org/kubevirt/virt-controller:1.2.1
  docker pull registry.opensuse.org/kubevirt/virt-controller:1.2.1-1.1
  docker pull registry.opensuse.org/kubevirt/virt-controller:1.2.1.8.17

Set DOCKER_CONTENT_TRUST=1 to enable image tag verification.