Build(deps-dev): Bump typing-extensions from 4.0.1 to 4.2.0 (#732)

Bumps [typing-extensions](https://github.com/python/typing) from 4.0.1 to 4.2.0.
- [Release notes](https://github.com/python/typing/releases)
- [Changelog](https://github.com/python/typing/blob/master/typing_extensions/CHANGELOG.md)
- [Commits](python/typing@4.0.1...4.2.0)

---
updated-dependencies:
- dependency-name: typing-extensions
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>