fix(vitest): use esm module resolution to resolve env

[danielroe]

Description

Sourcing from danielroe/nuxt-vitest#290 (comment)

While triaging issue I discovered that there's an issue with loading a pure ESM custom environment. It fails with the following issue:

Error: Cannot find module '/Users/daniel/code/vitest-environment-nuxt/playground/nuxt' imported from /Users/daniel/code/vitest-environment-nuxt/node_modules/.pnpm/[email protected][email protected][email protected]/node_modules/vitest/dist/vendor-environments.443ecd82.js
 ❯ new NodeError node:internal/errors:387:5
 ❯ finalizeResolution node:internal/modules/esm/resolve:330:11
 ❯ moduleResolve node:internal/modules/esm/resolve:907:10
 ❯ defaultResolve node:internal/modules/esm/resolve:1115:11
 ❯ nextResolve node:internal/modules/esm/loader:163:28
 ❯ ESMLoader.resolve node:internal/modules/esm/loader:841:30
 ❯ ESMLoader.getModuleJob node:internal/modules/esm/loader:424:18
 ❯ ESMLoader.import node:internal/modules/esm/loader:525:22
 ❯ importModuleDynamically node:internal/modules/esm/translators:110:35
 ❯ importModuleDynamicallyCallback node:internal/process/esm_loader:35:14

That is because local-pkg doesn't implement the ESM module resolution strategy but uses the CJS require.resolve strategy: https://github.com/antfu/local-pkg/blob/main/index.mjs#L11.

This instead uses mlly which wraps https://github.com/wooorm/import-meta-resolve to adopt the ESM module resolution strategy.

There are some other places in the code that could also be replaced.

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[sheremet-va]

LGTM 👍🏻

Thank you for looking into this 🙏🏻