Resolve ember 4 incompatibilities

[NullVoxPopuli]

Requires: https://github.com/html-next/vertical-collection/pull/370 ^ - any commits from here are also present in this diff until merged

For Ember 4

• we can't re-open Ember.Component (VerticalCollection.reopenClass)
• we can't use ember-cli-htmlbars@v5
• we can't use ember-data 3.12

Reproduction: https://github.com/NullVoxPopuli/vertical-collection-ember-4-ember-cli-htmlbars

• pnpm install
• ember s

[mixonic]

Ember 4.4 is supported by this library and tested on CI. Do you mean a later version of 4?

[NullVoxPopuli]

Deprecation-workflow is throwing errors on on 3.28 even: https://github.com/html-next/vertical-collection/runs/7395319955?check_suite_focus=true