chore(deps): update testing dependencies

Author: renovate[bot]

docs-app/package.json

@@ -86,7 +86,7 @@
     "ember-fetch": "^8.1.2",
     "ember-load-initializers": "^3.0.1",
     "ember-page-title": "^9.0.0",
-    "ember-qunit": "^8.0.0",
+    "ember-qunit": "^9.0.0",
     "ember-resolver": "^13.1.0",
     "ember-source": "~5.12.0",
     "ember-template-imports": "^3.1.2",