Included:
* DEV: Post-release cleanup
* DEV: Tests cleanup
* DEV: Import cleanup
* DEV: Drop a compatibility fix
* DEV: Use index_by
* DEV: Use ember imports
* DEV: Use discourseDebounce
* DEV: Use @action
* DEV: Use the optional chaining operator
* DEV: Fix an invalid test
* DEV: Use `discourseModule`
* DEV: Add .prettierrc
* DEV: Sync up the version number