test: add case for url.parse throwing a URIError

The auth property of a URL is decoded via decodeURIComponent,
which can throw a URIError. The test URL here will trigger this.

Adds documentation on the possible errors url.parse can throw.

PR-URL: https://github.com/nodejs/node/pull/12135


Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>