This container can be pulled via:
  docker pull registry.opensuse.org/isv/suse/edge/clusterapi/containerfile-sp6/cluster-api-controller:1.7.7
  docker pull registry.opensuse.org/isv/suse/edge/clusterapi/containerfile-sp6/cluster-api-controller:1.7.7-2.1
  docker pull registry.opensuse.org/isv/suse/edge/clusterapi/containerfile-sp6/cluster-api-controller:v1.7.7

Set DOCKER_CONTENT_TRUST=1 to enable image tag verification.