chore(deps-dev): bump ember-cli from 4.12.3 to 5.12.0

Bumps [ember-cli](https://github.com/ember-cli/ember-cli) from 4.12.3 to 5.12.0.
- [Release notes](https://github.com/ember-cli/ember-cli/releases)
- [Changelog](https://github.com/ember-cli/ember-cli/blob/master/CHANGELOG.md)
- [Commits](ember-cli/ember-cli@v4.12.3...v5.12.0)

---
updated-dependencies:
- dependency-name: ember-cli
  dependency-type: direct:development
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>