Reverse proxy docs - Add comment to use Docker DNS in nginx config example

[tvoirand]

Hi,

Thanks for your work on this great project!

The reverse proxy docs describe how to adapt the sample web server configuration in a scenario where the reverse proxy is running on the same server in a Docker container. In this scenario there are three options, the first one relying on host networking, and the next two relying on Docker bridge network's DNS name resolution.

I used the Docker bridge network's DNS method with nginx. But without explicitly telling nginx to use the Docker DNS server with a resolver 127.0.0.11 directive, this method fails with the nginx logs giving "no resolver defined to resolve nextcloud-aio-apache".
The resolver directive is not mentioned in the nginx config example. Adding it as an optional/commented line could help.

• It does add yet another optional/commented line in the config example, so I guess adding this is a compromise between 1/ keeping the example simple and letting the user adapt by themself versus 2/ helping the user by making the example exhaustive at the risk of cluttering with too much information.

• I'm not an expert of nginx in Docker containers, it's possible that some other aspect of my setup made this resolver 127.0.0.11 directive necessary.

• Resolves: #

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[Zoey2936]

resolver should not be needed since the proxy_pass goes to an ip, not a hostname/domain