chore(deps): update actions/setup-python action to v5.6.0

Author: renovate[bot]

.github/workflows/validate.yaml

@@ -8,6 +8,6 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: actions/setup-python@v5
+      - uses: actions/setup-python@a26af69be951a213d495a4c3e4e4022e16d87065 # v5.6.0
       - run: pip install pre-commit
       - run: pre-commit validate-manifest .pre-commit-hooks.yaml