* Ember `addon/auth` upgrade v4.4.1...v4.12.2
* Update .npmignore
* refactor: 💡 Quick refactor
Refactor `.eslintrc.js` to current `ecmaVersion` and use latest
`babelOptions`. Revert `.prettier.js` to use previous overrides. Setup
scripts to use `concurrently` instead of `npm-run-all`
* refactor: 💡 removed `npm-run-all`
Removed `npm-run-all` from package.json