Bump ember-source from 3.20.3 to 4.12.3

Bumps [ember-source](https://github.com/emberjs/ember.js) from 3.20.3 to 4.12.3.
- [Release notes](https://github.com/emberjs/ember.js/releases)
- [Changelog](https://github.com/emberjs/ember.js/blob/main/CHANGELOG.md)
- [Commits](emberjs/ember.js@v3.20.3...v4.12.3)

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

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

package.json

@@ -130,7 +130,7 @@
     "ember-router-scroll": "^3.3.7",
     "ember-simple-auth": "^4.2.2",
     "ember-simple-auth-token": "^5.3.0",
-    "ember-source": "3.20.3",
+    "ember-source": "4.12.3",
     "ember-table": "^2.2.3",
     "ember-template-lint": "^2.21.0",
     "ember-truth-helpers": "^3.1.1",