Bump the actions group in /requirements with 1 update

Bumps the actions group in /requirements with 1 update: [mypy](https://github.com/python/mypy).


Updates `mypy` from 1.8.0 to 1.9.0
- [Changelog](https://github.com/python/mypy/blob/master/CHANGELOG.md)
- [Commits](python/mypy@v1.8.0...1.9.0)

---
updated-dependencies:
- dependency-name: mypy
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: actions
...

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

requirements/typecheck.txt

@@ -1 +1 @@
-mypy==1.8.0
+mypy==1.9.0