chore(deps): update dependency ember-source to v6

Author: renovate[bot]

packages/test-app/package.json

@@ -57,7 +57,7 @@
     "ember-page-title": "8.2.4",
     "ember-qunit": "8.1.1",
     "ember-resolver": "13.1.1",
-    "ember-source": "5.12.0",
+    "ember-source": "6.5.0",
     "ember-template-lint": "7.9.1",
     "ember-welcome-page": "7.0.2",
     "eslint": "9.30.1",