Build(deps): Bump actions/setup-python

Bumps the actions-infrastructure group with 1 update: [actions/setup-python](https://github.com/actions/setup-python).


Updates `actions/setup-python` from 5 to 6
- [Release notes](https://github.com/actions/setup-python/releases)
- [Commits](actions/setup-python@v5...v6)

---
updated-dependencies:
- dependency-name: actions/setup-python
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: actions-infrastructure
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.github/workflows/tox.yml

@@ -29,7 +29,7 @@ jobs:
       with:
         fetch-depth: 0
     - name: Set up Python 3
-      uses: actions/setup-python@v5
+      uses: actions/setup-python@v6
       with:
         python-version: 3
     - name: Display Python version
@@ -131,7 +131,7 @@ jobs:
           sudo apt update
           sudo apt install -y --no-install-recommends graphviz
       - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v5
+        uses: actions/setup-python@v6
         with:
           python-version: ${{ matrix.python-version }}
       - name: Display Python version