Roadmap for Symfony 6 & Stimulus 3 support

[weaverryan]

Hi!

Stimulus 3 has been released (if you're unaware, it's a few nice feature, but mostly, the library was renamed from stimulus to @hotwired/stimulus) and Symfony 6 is around the corner. Here is what I think we should do:

A) Make one last 1.x release of symfony/ux with Symfony 6 support #160 (we decided to skip this - if you're using Symfony 6, you'll use 2.0 of the symfony/ux libraries)
B) Create 1.x and 2.x branches on symfony/ux (skipped this also - keep main branch only for now)
C) Make a 2.0 release of symfony/ux, stimulus-bridge, stimulus-testing
- Merge Stimulus 3 PR (#141, symfony/stimulus-testing#4, symfony/stimulus-bridge#48)
- new build system / typescript (#156)
- Chartjs upgrade (#126)
- bump PHP min version to 8.0

Blockers for the 2.0 release:

• Upgrading all packages to Stimulus 3 #141
• Using Typescript & Centralizing Builds #156
• Update chart.js dependency #126 (not a block but would be great to have)
• PR to update the recipe for WebpackEncoreBundle to install @hotwired/stimulus v3

[norkunas]

This can be closed I think