Update ruff requirement from >=0.8 to >=0.15.12

Updates the requirements on [ruff](https://github.com/astral-sh/ruff) to permit the latest version.
- [Release notes](https://github.com/astral-sh/ruff/releases)
- [Changelog](https://github.com/astral-sh/ruff/blob/main/CHANGELOG.md)
- [Commits](astral-sh/ruff@0.8.0...0.15.12)

---
updated-dependencies:
- dependency-name: ruff
  dependency-version: 0.15.12
  dependency-type: direct:development
...

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

Author: dependabot[bot]

requirements_dev.txt

@@ -1,5 +1,5 @@
 pre-commit==4.5.1
-ruff>=0.8
+ruff>=0.15.12
 homeassistant
 pyporscheconnectapi
 pytest