Move to ESM

[pixelastic]

With all the underlying packages moving to ESM, I will have to do the same at some point.

• Jest still do not understands ESM in its configuration files. Having two different systems in the same codebase is going to be a pain, so maybe I should wait until Jest is fully ESM compliant.
  • Support ESM resolution browserify/resolve#222
  • Meta: Native support for ES Modules jestjs/jest#9430
• VisualCode seems to be able to help in the refactoring: https://twitter.com/holtbt/status/995528779085721602

[pixelastic]

Great point in GoogleChrome/lighthouse#12689

The package.json type field is what enables esmodules (we don't want to do .mjs), and luckily the nearest package.json file is used, so during the transition we can just write {type: "module"} files where necessary.

[pixelastic]

https://formidable.com/blog/2021/node-esm-and-exports/