Describe the bug
I'm a little new to Traefik so I apologize if I'm off base here. I'm going through the guide and setting up FreshRSS in Docker+Traefikv2.7(r.c-something at the moment). The FreshRSS run command portion of the documentation uses strange label names to me. From what I can tell, they're from version 1 of Traefik and not applicable to version 2. Edit: Just realized the documentation is tagged v1.7 so it is for an older verison.

I've tinkered around with the labels, and here's what I propose we change them to on the documentation:

--label traefik.port=80 \
--label traefik.http.services.freshrss.loadbalancer.server.port=80 \

--label traefik.frontend.rule='Host:freshrss.example.net' \
--label traefik.http.routers.freshrss.rule=Host(``freshrss.example.net``) (I don't know how to escape backticks... Pretend they aren't doubled)

If you use Prefixes:
--label traefik.http.routers.freshrss.rule=Host(``freshrss.example.net``) && PathPrefix(``/freshrss``)
--label traefik.http.middlewares.freshrss-stripprefix.stripprefix.prefixes=/freshrss \
--label traefik.http.routers.freshrss.middlewares=freshrss-stripprefix@docker \

I need someone else to confirm the STS labels as I haven't played with those yet.