chore(deps): update mypy requirement from ~=1.8 to ~=1.9 (#233)

Updates the requirements on [mypy](https://github.com/python/mypy) to permit the latest version.
- [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
...

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

requirements-testing.txt

@@ -8,7 +8,7 @@ pytest-xdist == 3.5.*
 black[jupyter] ~= 23.12
 rich == 13.7.*
 types-python-dateutil ~= 2.9
-mypy ~= 1.8
+mypy ~= 1.9
 types-requests ~= 2.31
 ruff ~= 0.3.3
 twine ~= 5.0