Decommission dokku

I don't use it, still. I have a better plan for doing this in future anyway...

ansible/host_vars/pve-docker/main.yml

@@ -3,7 +3,6 @@ private_ip: "{{ pve_hosts.docker.ip }}"
 traefik_provider_jellyfin: true
 traefik_provider_homeassistant: true
 traefik_provider_grafana: true
-traefik_provider_dokku: true
 traefik_provider_uptime_kuma: true
 
 with_fail2ban: true