Bump @testing-library/react from 12.1.5 to 16.2.0 in /frontend

Bumps [@testing-library/react](https://github.com/testing-library/react-testing-library) from 12.1.5 to 16.2.0.
- [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@v12.1.5...v16.2.0)

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

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