build(deps-dev): bump @testing-library/react in /frontend

Bumps [@testing-library/react](https://github.com/testing-library/react-testing-library) from 15.0.6 to 16.0.0.
- [Release notes](https://github.com/testing-library/react-testing-library/releases)
- [Changelog](https://github.com/testing-library/react-testing-library/blob/main/CHANGELOG.md)
- [Commits](testing-library/react-testing-library@v15.0.6...v16.0.0)

---
updated-dependencies:
- dependency-name: "@testing-library/react"
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

frontend/package.json

@@ -55,7 +55,7 @@
     "@storybook/react-vite": "^8.0.10",
     "@tanstack/router-devtools": "^1.31.27",
     "@tanstack/router-vite-plugin": "^1.31.18",
-    "@testing-library/react": "^15.0.6",
+    "@testing-library/react": "^16.0.0",
     "@types/node": "^20.14.6",
     "@types/react": "^18.3.3",
     "@types/react-dom": "^18.3.0",