remove systemd timer which is not necessary with tutor 11 and above
Tutor 11 uses caddy for HTTPS, which means we can drop the systemd timer that gets new certificates and restarts nginx. Extra benefit: less downtime, most likely!
For reference, Tutor docs: https://docs.tutor.overhang.io/configuration.html?highlight=https#ssl-tls-certificates-for-https-access