test: remove NODE_DEBUG in global module loading test

Otherwise the debug log output might be mixed up with
the expected errors and the assertion matching the error
message would fail.

Backport-PR-URL: https://github.com/nodejs/node/pull/19374
PR-URL: https://github.com/nodejs/node/pull/19177
Refs: https://github.com/nodejs/node/pull/19112


Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>