Upgrade ruff to 0.15.6

Author: tleonhardt

.pre-commit-config.yaml

@@ -9,7 +9,7 @@ repos:
       - id: trailing-whitespace
 
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: "v0.15.4"
+    rev: "v0.15.6"
     hooks:
       - id: ruff-format
         args: [--config=ruff.toml]