coverage: use process._rawDebug() during setup

console is not ready to use at this point in the bootstrapping
process, so switch to process._rawDebug() instead.

PR-URL: https://github.com/nodejs/node/pull/25289
Fixes: https://github.com/nodejs/node/issues/25287


Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Yuta Hiroto <hello@hiroppy.me>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>