Bump mypy from 1.3.0 to 1.4.0 (#295)

Bumps [mypy](https://github.com/python/mypy) from 1.3.0 to 1.4.0.
- [Commits](python/mypy@v1.3.0...v1.4.0)

---
updated-dependencies:
- dependency-name: mypy
  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>

Author: dependabot[bot]

setup.cfg

@@ -34,7 +34,7 @@ exclude =
 build-tools =
     grpcio-tools==1.55.0
 dev =
-    mypy==1.3.0
+    mypy==1.4.0
     mypy-protobuf==3.4.0
     pre-commit==3.3.3
     pytest==7.3.2