Bump ember-source from 6.5.0 to 6.6.0 (#380)

Bumps [ember-source](https://github.com/emberjs/ember.js) from 6.5.0 to 6.6.0.
- [Release notes](https://github.com/emberjs/ember.js/releases)
- [Changelog](https://github.com/emberjs/ember.js/blob/main/CHANGELOG.md)
- [Commits](https://github.com/emberjs/ember.js/commits)

---
updated-dependencies:
- dependency-name: ember-source
  dependency-version: 6.6.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]