test: missing fixture test-esm-pkg-over-ext.mjs

[bcoe]

I think I figured out the issue causing the test suite to fail (see #15276) with the following error:

=== release test-esm-pkg-over-ext ===                                          
Path: es-module/test-esm-pkg-over-ext
(node:12584) ExperimentalWarning: The ESM module loader is experimental.
Error: module ../fixtures/module-pkg-over-ext/inner not found
    at module.exports (internal/loader/search.js:16:12)
    at resolveRequestUrl (internal/loader/resolveRequestUrl.js:81:13)
    at Loader.getModuleJob (internal/loader/Loader.js:50:27)
    at ModuleWrap.module.link (internal/loader/ModuleJob.js:30:25)
    at linked (internal/loader/ModuleJob.js:28:21)
    at <anonymous>

1. there was a missing fixture fixtures/module-pkg-over-ext/inner/package.json.
2. I think the first import in the test should be ../fixtures/module-pkg-over-ext/inner/package vs. ../fixtures/module-pkg-over-ext/inner, or at least at this time importing a directory does not seem to default to package.json if no index.js is found (is this expected behavior @bmeck?).

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• commit message follows commit guidelines

Affected core subsystem(s)

test,es-module

[bmeck]

kind of the inverse, there should be an inner.js

[bmeck]

the subject of #14990 is what this fixture is supposed to be about

[bcoe]

@bmeck sounds like there's a bit more work than just adding the fixture, following #14990. Want me to close this, and I can rebase #15276 once tests are passing?

[bmeck]

sure, we can wait and rebase