test: add known_test request with Unicode in the URL

This test currently fails. It illustrates that Unicode in the URL does
not arrive intact to the server, there is silent data corruption along
the way at some point.

This test is for the issue https://github.com/nodejs/node/issues/13296.

PR-URL: https://github.com/nodejs/node/pull/13297


Reviewed-By: James M Snell <jasnell@gmail.com>