Don't change the port during an update

[yubiuser]

Duplicate of

Detect non-standard lighttpd port during update

I run lighttpd for pihole admin on a non-standard port (eg. 8080). Every time I update pihole with "pihole -up" it resets the server.port configuration setting in /etc/lighttpd/lighttpd.conf to use port 80, which means that the service won't restart and I have to go and manually update the lighttpd config. Since pihole updates are frequent, it'd be really nice if the update process could detect whether lighttpd is running on a port other than 80 and NOT change the server.port setting if so.