https: support rejectUnauthorized for unix sockets

This commit allows self signed certificates to work with
unix sockets by forwarding the rejectUnauthorized option.

Fixes: https://github.com/nodejs/node/issues/13470
PR-URL: https://github.com/nodejs/node/pull/13505


Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: Sam Roberts <vieuxtech@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Daniel Bevenius <daniel.bevenius@gmail.com>