This container can be pulled via:
  docker pull registry.opensuse.org/home/defolos/bci/staging/sle-15-sp6/6-1046/containerfile/suse/postfix:3.8
  docker pull registry.opensuse.org/home/defolos/bci/staging/sle-15-sp6/6-1046/containerfile/suse/postfix:3.8-1.72

Set DOCKER_CONTENT_TRUST=1 to enable image tag verification.