Bump ruff from 0.4.10 to 0.6.8

Bumps [ruff](https://github.com/astral-sh/ruff) from 0.4.10 to 0.6.8.
- [Release notes](https://github.com/astral-sh/ruff/releases)
- [Changelog](https://github.com/astral-sh/ruff/blob/main/CHANGELOG.md)
- [Commits](astral-sh/ruff@v0.4.10...0.6.8)

---
updated-dependencies:
- dependency-name: ruff
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

devdeps.txt

@@ -1,6 +1,6 @@
 # dev
 black
-ruff==0.4.10
+ruff==0.6.8
 
 # docs
 mkdocs