Bump typing-extensions from 4.2.0 to 4.3.0 in /dependencies/default

Bumps [typing-extensions](https://github.com/python/typing_extensions) from 4.2.0 to 4.3.0.
- [Release notes](https://github.com/python/typing_extensions/releases)
- [Changelog](https://github.com/python/typing_extensions/blob/main/CHANGELOG.md)
- [Commits](python/typing_extensions@4.2.0...4.3.0)

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

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

Author: dependabot[bot]

dependencies/default/constraints.txt

@@ -20,5 +20,5 @@ sortedcontainers==2.4.0
 tomli==2.0.1
 trio==0.21.0
 typed-ast==1.5.4
-typing_extensions==4.2.0
+typing_extensions==4.3.0
 zipp==3.8.0