IpAddressQuestion & HostnameQuestion: Toolbox::getRemoteIpAddress() doesn't support reverse proxies

[landure]

Code of Conduct

• I agree to follow this project's Code of Conduct

Is there an existing issue for this?

• I have searched the existing issues

GLPI Version

11.0.1

Plugin version

1.0

Bug description

IpAddressQuestion and HostnameQuestion use GLPI Toolbox::getRemoteIpAddress() to determine the user IP address.
It returns $_SERVER["REMOTE_ADDR"].

This is an issue when hosting GLPI behing a reverse proxy such as Traefik.
The correct value is this case is (as seen in GLPI's Auth.php):

 $ip = getenv("HTTP_X_FORWARDED_FOR") ?: getenv("REMOTE_ADDR");

Please add an option to customize the env value used to get the user IP address.
Or add an EnvironmentVariableQuestion feature to allow querying HTTP headers.

Thank you for you work.