Update actions/setup-python action to v6

Author: renovate[bot]

action.yml

@@ -14,7 +14,7 @@ runs:
   using: "composite"
   steps:
     - name: Set up Python
-      uses: actions/setup-python@v4
+      uses: actions/setup-python@v6
       with:
         python-version: '3.11'