Sync vanilla images

There isn't a systemd image for arm and I like the appearance of less
magic.  Nest stage 0 will converge on a systemd profile.

.gitlab-ci.yml

 ---
+stages:
+  - 'sync'
+
 default:
   image: 'quay.io/containers/buildah'
   before_script:
     - 'buildah login -u "$CI_REGISTRY_USER" -p "$CI_REGISTRY_PASSWORD" "$CI_REGISTRY"'
 
-stages:
-  - 'sync'
-
-'Sync gentoo/stage3:amd64-systemd':
+'Sync gentoo/stage3:amd64':
   stage: 'sync'
   script:
-    - 'buildah pull gentoo/stage3:amd64-systemd'
-    - 'buildah tag gentoo/stage3:amd64-systemd "${CI_REGISTRY_IMAGE}:amd64-systemd"'
-    - 'buildah push "${CI_REGISTRY_IMAGE}:amd64-systemd"'
+    - 'buildah pull gentoo/stage3:amd64'
+    - 'buildah tag gentoo/stage3:amd64 "${CI_REGISTRY_IMAGE}:amd64"'
+    - 'buildah push "${CI_REGISTRY_IMAGE}:amd64"'