enable cert-manager based config for the tn registry certificates

We created them by hand for now, after generation with certbot.

They have the DNS config for all the services we had in the old cluster (openstack+registry+minio everything). There are two certs today:

In reality we only need harbor-tn-harbor-ingress, tn-k8s-node-1-certs was created manually but should no longer be needed (by harbor or minio).