Convert to v2 format addons in app blueprint

[SergeAstapov]

Scope of this ticket is to track progress converting addons from default app and addon blueprints to v2 format.

Addons with runtime only functionality, first candidates for conversion:

• ember-welcome-page
• ember-page-title https://github.com/ember-cli/ember-page-title/releases/tag/v8.0.0
• @ember/test-helpers WIP V2 conversion emberjs/ember-test-helpers#1381
• @glimmer/component
• @glimmer/tracking
• ember-data
• ember-export-application-global (not needed due to Remove ember-export-application-global addon from app blueprint #9825)
• ember-load-initializers Convert to V2 addon ember-load-initializers#303
• ember-maybe-import-regenerator (not needed due to update dependencies before beta release #9604)
• ember-resolver WIP Convert to TypeScript ember-resolver#852
• ember-source (larger lift, already planned during v4 lifecycle)
• qunit-dom released as v2 in v3.0.0

Addons with build-time functionality, conversion may not be straightforward or not needed:

• @ember/optional-features
  Build-time features validation, has ember-cli commands feature:list, feature:enable, feature:disable
• @embroider/compat (not an addon)
• @embroider/core (not an addon)
• @embroider/webpack (not an addon)
• broccoli-asset-rev (unmaintained, and not part of the Embroider future)
• ember-auto-import
• ember-cli (not an addon)
• ember-cli-app-version
• ember-cli-babel
• ember-cli-dependency-checker
• ember-cli-htmlbars
• ember-cli-inject-live-reload
• ember-cli-sri (archived, and under Embroider, we should see if we can leverage something like https://www.npmjs.com/package/webpack-subresource-integrity)
• ember-cli-terser (not used/needed under Embroider)
• ember-fetch
• ember-qunit - released as v2 in v8.0.0
• ember-template-lint
• loader.js (may be converted if we get rid of dynamism from index.js)

[bertdeblock]

@SergeAstapov You can tick off the ember-export-application-global one. #9825 (comment) is merged 🎉

[bertdeblock]

@SergeAstapov ember-maybe-import-regenerator has already been deleted as well some time ago:
#9604

[bertdeblock]

FYI, ember-template-lint is not an addon.

[bertdeblock]

Striked through ember-cli-sri, ember-cli and broccoli-asset-rev as well.

[jelhan]

ember-qunit has been converted to v2 addon in recent v8.0.0 release as well.

[NullVoxPopuli]

as has qunit-dom, in v3.0.0