the scoped mixin no longer depends on it directly

It has new API which we want to use.

Newest Ubuntu switched Firefox to a snap, which breaks karma.

Try to use playwright to download and cache firefox/chromium
and use those for karma.

Compared to puppeteer where we did this some time ago this caches
the browsers globally, and only downloads them when we start the tests.

This reverts commit 6324718b.

This reverts commit 3716524b.

Just change all imports and dependencies.

No longer needs babel, but requries an alpha version of the typescript plugin
for eslint 8 support

These are all transitive dependencies (or unused) so they get pulled in
anyway.

In newer versions there is now a normal method for this which also supports
dynamically added components.

The static version is deprecated and removed in 2.0, so we need to port here.

It's confusing that there are two lock files in this repo and two
overlapping workspaces. Ideally everything should be in sync.

This has proper support for rollup while providing the same API.

This is what open-wc recommends now and uses in their @open-wc/testing package