reg-tool.sh doesn't seem to handle RBAC

I'm getting these errors in the create-certs pod:

```
╰ 21:44:49 $ kubectl logs create-certs-f24ng
Error from server (Forbidden): secrets "registry-cert" is forbidden: User "system:serviceaccount:default:default" cannot delete resource "secrets" in API group "" in the namespace "default"
Error from server (Forbidden): secrets "registry-cert" is forbidden: User "system:serviceaccount:default:default" cannot delete resource "secrets" in API group "" in the namespace "kube-system"
Error from server (Forbidden): secrets "registry-key" is forbidden: User "system:serviceaccount:default:default" cannot delete resource "secrets" in API group "" in the namespace "kube-system"
Generating a 4096 bit RSA private key
.................................................................................++
..............................................................................................................................................++
writing new private key to 'certs/domain.key'
-----
Error from server (Forbidden): secrets is forbidden: User "system:serviceaccount:default:default" cannot create resource "secrets" in API group "" in the namespace "default"
```

I don't see any mention of "rbac" in the script, so I'm guessing it was written before RBAC was a thing.