test: expand test coverage for url.js

Add url example with more than 255 characters in the hostname
of the url.

PR-URL: https://github.com/nodejs/node/pull/8976


Reviewed-By: Gibson Fahnestock <gibfahn@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Ilkka Myller <ilkka.myller@nodefield.com>
Reviewed-By: James M Snell <jasnell@gmail.com>