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

Author: renovate[bot]

.github/workflows/checks.yml

@@ -110,7 +110,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5.0.0
-      - uses: actions/setup-python@v5
+      - uses: actions/setup-python@v6
         with:
           python-version: "3.12"
       - name: Download coverage reports