7.0 planning

[kategengler]

Remove AMD Bundles

WIP Branch

Checklist

• Fix using-amd-bundles deprecation cannot be silenced nor handled in new classic app in 6.10 #21064
• Remove AMD Bundles
• Update blueprint babel config to remove this line https://github.com/ember-cli/ember-new-output/blob/master/babel.config.cjs#L13 and to ensure babel-plugin-ember-template-compilation is >= 3.1.0

Remove Barrel file

WIP Branch

Remove unused parts of ember-testing package

Parts of the ember-testing package support the very old style of testing from before RFC #232 Simplify QUnit Testing API that introduced the setup*Test methods to replace moduleFor* methods in testing. We never deprecated this old style of testing but from experimentation I believe we have accidentally broken it long, long ago and it has been undocumented for multiple majors. Because of this we believe we can clean up the old code lingering.

[kategengler]

@ef4 and I found in our exploration last week that both of these are blocked on #21064