chore(web-extension-v2): remove package

[andy-blum]

[!NOTE] This PR is a part of my exploration into the devtools to understand how they work, how to update them for use with the next version of Carbon and carbon-based libraries, and how to make them more maintainable going forward. Full documentation is available here (w3ID required)

This PR is a followup to #286. Since firefox 121 and chrome 121, browsers are more forgiving with unrecognized keys in the manifest.json file's background property. (source)

With this limitation removed, all other APIs used by this extension appear to be cross-browser ready.

Changelog

Changed

• web-extension v3 is compatible with chrome & firefox

Removed

• web-extension v2 is removed

Testing / Reviewing

• yarn install
• yarn build
• cd packages/web-extension
• yarn launch:chrome or yarn launch:firefox
• Ensure extension functionality works correctly

[motou]

Please take a look at the building phrase of the devtools since the PR check is failed.