chore(deps-dev): bump ruff in the test-dependencies group

Bumps the test-dependencies group with 1 update: [ruff](https://github.com/astral-sh/ruff).


Updates `ruff` from 0.15.20 to 0.15.21
- [Release notes](https://github.com/astral-sh/ruff/releases)
- [Changelog](https://github.com/astral-sh/ruff/blob/main/CHANGELOG.md)
- [Commits](astral-sh/ruff@0.15.20...0.15.21)

---
updated-dependencies:
- dependency-name: ruff
  dependency-version: 0.15.21
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: test-dependencies
...

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Author: dependabot[bot]