Update actions/setup-python action to v6

Author: renovate[bot]

.github/workflows/ci.yml

@@ -18,7 +18,7 @@ jobs:
         with:
           version: "0.6.0"
       - name: Setup Python
-        uses: actions/setup-python@v5
+        uses: actions/setup-python@v6
         with:
           python-version-file: "pyproject.toml"
       - name: Install dependencies