Logout redirect should use request port or relative URI

[ajtucker]

On logging out, the user agent is redirected after a POST to some path using a 3xx response code. The Location in the response is determined from the original request, using the same scheme and host, but doesn't consider the port.

This causes problems when using a non-standard port, e.g. when not using a proxy.

Note that it appears that the Location header no longer needs to be an absolute URI. In RFC 2616 that was the case, but in newer RFC 7231 and RFC 9110 this was relaxed and Location is now a URI reference and can be relative.

[der]

Some of the registry functionality (redirects, forwards) depending on having a linked proxy server, so running without a proxy server isn't officially supported. Though certainly true that for simple cases where you don't need those services then running raw can be useful for test purposes.