build(deps): bump ruff from 0.12.8 to 0.12.9 in /requirements (#1259)

Bumps [ruff](https://github.com/astral-sh/ruff) from 0.12.8 to 0.12.9.
- [Release notes](https://github.com/astral-sh/ruff/releases)
- [Changelog](https://github.com/astral-sh/ruff/blob/main/CHANGELOG.md)
- [Commits](https://github.com/astral-sh/ruff/compare/0.12.8...0.12.9)

---
updated-dependencies:
- dependency-name: ruff
  dependency-version: 0.12.9
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

requirements/requirements.txt

@@ -6,4 +6,4 @@ ecos == 2.0.14
 pytest == 8.4.1 # For unit test
 pytest-xdist == 3.8.0 # For unit test
 mypy == 1.17.1 # For unit test
-ruff == 0.12.8 # For unit test
+ruff == 0.12.9 # For unit test