Config: Wrong subPath config result in endless loop

### What happened? ``` # The full public facing url root_url = %(protocol)s://%(domain)s:%(http_port)s/grafana # Serve Grafana from subpath specified in `root_url` setting. By default it is set to `false` for compatibility reasons. serve_from_sub_path = false ``` setting this config, the endless login will appear. ### What did you expect to happen? no endless login ### Did this work before? i don't know ### How do we reproduce it? 1. use config i post 2. enter localhost:3000 3. ### Is the bug inside a dashboard panel? no ### Environment (with versions)? Grafana: 11.5.1 OS: macos Browser: chrome ### Grafana platform? None ### Datasource(s)? _No response_