Bump types-ujson from 4.2.0 to 4.2.1 in /tools

Bumps [types-ujson](https://github.com/python/typeshed) from 4.2.0 to 4.2.1.
- [Release notes](https://github.com/python/typeshed/releases)
- [Commits](https://github.com/python/typeshed/commits)

---
updated-dependencies:
- dependency-name: types-ujson
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

tools/requirements_mypy.txt

@@ -8,5 +8,5 @@ types-PyYAML==6.0.4
 types-requests==2.27.11
 types-setuptools==57.4.9
 types-six==1.16.11
-types-ujson==4.2.0
+types-ujson==4.2.1
 typing-extensions==4.1.1