Use CI_REPOSITORY_URL as origin for kustomize-units artifact

We need to use a bash expansion to remove the reference to gitlab-token

oras manifest fetch registry.gitlab.com/sylva-projects/sylva-core/kustomize-units:0.0.0-git-cf8a4f34 | jq .annotations
{
  "org.opencontainers.image.created": "2023-10-06T09:18:20Z",
  "org.opencontainers.image.revision": "/cf8a4f340902d37c467d7f6c911fde18a7d7e3a6",
  "org.opencontainers.image.source": "https://gitlab.com/sylva-projects/sylva-core.git"
}

part: https://gitlab.com/sylva-projects/sylva-elements/diskimage-builder/-/issues/39