chore(deps): update actions/setup-python action to v6

Author: renovate[bot]

.github/workflows/pr.yaml

@@ -14,7 +14,7 @@ jobs:
         python: ["3.10", "3.11", "3.12", "3.13"]
     steps:
       - name: Setup Python
-        uses: actions/setup-python@v5
+        uses: actions/setup-python@v6
         with:
           python-version: ${{ matrix.python }}
       - name: Install tox and any other packages