This container can be pulled via:
  docker pull registry.opensuse.org/virtualization/containerfile/kubevirt/virt-controller:1.4.0
  docker pull registry.opensuse.org/virtualization/containerfile/kubevirt/virt-controller:1.4.0-Virt.1699.193.28
  docker pull registry.opensuse.org/virtualization/containerfile/kubevirt/virt-controller:1.4.0.Virt.1699.29.226

Set DOCKER_CONTENT_TRUST=1 to enable image tag verification.