Bump @testing-library/jest-dom in /fitbit_challenges/frontend

Bumps [@testing-library/jest-dom](https://github.com/testing-library/jest-dom) from 6.4.5 to 6.4.6.
- [Release notes](https://github.com/testing-library/jest-dom/releases)
- [Changelog](https://github.com/testing-library/jest-dom/blob/main/CHANGELOG.md)
- [Commits](testing-library/jest-dom@v6.4.5...v6.4.6)

---
updated-dependencies:
- dependency-name: "@testing-library/jest-dom"
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

fitbit_challenges/frontend/package.json

@@ -8,7 +8,7 @@
     "@apollo/react-testing": "^4.0.0",
     "@headlessui/react": "^2.0.4",
     "@heroicons/react": "^2.1.3",
-    "@testing-library/jest-dom": "^6.4.5",
+    "@testing-library/jest-dom": "^6.4.6",
     "@testing-library/react": "^16.0.0",
     "@testing-library/user-event": "^14.5.2",
     "@types/node": "^20.14.2",