test: fix ESM test

The previously landed commit was broken and it’s too late
to force-push. Fixing up the test seems to work.

Refs: https://github.com/nodejs/node/pull/21352

PR-URL: https://github.com/nodejs/node/pull/21605


Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>