Upgrade ember a11y testing to v7 (#2470)

* chore: 🤖 update ember-a11y-testing and @ember/test-helpers

* chore: 🤖 upgrade to v7

* chore: 🤖 upgrade deps and force resolutions to fix errors

* chore: 🤖 fix ember-a11y errors due to summary title not showing

* chore: 🤖 fix yarn.lock

addons/auth/package.json

@@ -21,7 +21,7 @@
     "doc:toc": "doctoc README.md"
   },
   "dependencies": {
-    "ember-cli-babel": "^7.26.11",
+    "ember-cli-babel": "^8.2.0",
     "ember-cli-htmlbars": "^6.2.0",
     "ember-fetch": "^8.1.1",
     "ember-simple-auth": "^4.2.2"
@@ -31,7 +31,7 @@
     "@babel/plugin-proposal-decorators": "^7.21.0",
     "@ember/optional-features": "^2.0.0",
     "@ember/string": "^3.0.1",
-    "@ember/test-helpers": "^2.9.3",
+    "@ember/test-helpers": "^3.3.1",
     "@embroider/test-setup": "^2.1.1",
     "@glimmer/component": "^1.1.2",
     "@glimmer/tracking": "^1.1.2",