Bump ember-web-app from 3.0.1 to 4.0.0

Bumps [ember-web-app](https://github.com/zonkyio/ember-web-app) from 3.0.1 to 4.0.0.
- [Release notes](https://github.com/zonkyio/ember-web-app/releases)
- [Changelog](https://github.com/zonkyio/ember-web-app/blob/master/CHANGELOG.md)
- [Commits](zonkyio/ember-web-app@v3.0.1...v4.0.0)

Signed-off-by: dependabot-preview[bot] <[email protected]>

Author: dependabot-preview[bot]