Proxy via nginx to path doesn't work

[jzielke84]

Describe the bug

When setting SITE_URL to something like https://myhost.domain.com/infisical the gui still tries to load ressources from https://myhost.domain.com e.g. https://myhost.domain.com/images/loading/loading.gif.

My nginx is passing everything to http://localhost:3000 (that's where infisical runs):

      location /infisical {
            proxy_pass http://localhost:3000;
            proxy_redirect off;
            proxy_set_header Host $http_host;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
            proxy_set_header X-Real-IP $remote_addr;
        expires -1;
      }

To Reproduce

Steps to reproduce the behavior:

1. Install infisical using docker
2. Install nginx reverse proxy
3. Set SITE_URL

Expected behavior

Access infisical by subdirectory. Also expect some kind of documentation for using reverse proxies. No info on custom headers (if needed) or anything else.