Allow non-relative imports starting with src/ or vendor/

[fredrikekelund]

Related issues

• Fixes https://github.com/Automattic/dotcom-forge/issues/10292

Proposed Changes

There's currently no way to use absolute import paths in Studio. This PR changes that by updating the Typescript, ESLint and Webpack configs to allow import paths starting with src/ or vendor/.

This enables us to use a similar approach as Calypso, where import paths can start with calypso/.

This was something I set up while working on #826. That PR introduces a new folder—src/stores—and I figured having a consistent import path for it would be nice.

Testing Instructions

1. Restart your editor after running npm install
2. Pick a file and change the import paths to be absolute
3. Ensure that the editor doesn't complain and that npm start works as expected

Pre-merge Checklist

• Have you checked for TypeScript, React or other console errors?

[wojtekn]

The change looks correct, and works as expected. IDE allows for both type of paths.

Also, it shows where path could be shortened e.g.:

Thanks for that improvement!