chore(ci): the k8s cluster uses the root container

v7.next.forgejo.org is legacy and was created with a root container
image as an exception.

https://code.forgejo.org/infrastructure/k8s-cluster/issues/30#issuecomment-17221

.forgejo/workflows/publish-release.yml

@@ -66,7 +66,6 @@ jobs:
           url: https://placeholder:${{ secrets.TOKEN_NEXT_DIGEST }}@code.forgejo.org/infrastructure/next-digest
           ref_name: '${{ github.ref_name }}'
           image: 'codeberg.org/forgejo-experimental/forgejo'
-          tag_suffix: '-rootless'
 
       - name: set up go for the DNS update below
         if: vars.ROLE == 'forgejo-experimental' && secrets.OVH_APP_KEY != ''