Bump @testing-library/jest-dom in /templates/react-javascript

Bumps [@testing-library/jest-dom](https://github.com/testing-library/jest-dom) from 6.4.2 to 6.6.2.
- [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@v6.4.2...v6.6.2)

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

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]