Bump actions/setup-python from 5 to 6

Bumps [actions/setup-python](https://github.com/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
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: actions/setup-python@v5
+      - uses: actions/setup-python@v6
         with: { python-version: "3.11" }
       - name: system deps (OpenMP runtime for LightGBM/XGBoost via flaml)
         run: sudo apt-get update && sudo apt-get install -y --no-install-recommends libgomp1
@@ -29,7 +29,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: actions/setup-python@v5
+      - uses: actions/setup-python@v6
         with: { python-version: "3.11" }
       - run: pip install -e ".[dev]"
       # Compares DuckDB reshape output to the checked-in, PR-reviewed golden fixture.
@@ -47,7 +47,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: actions/setup-python@v5
+      - uses: actions/setup-python@v6
         with: { python-version: "3.11" }
       # Audit the FULL resolved graph INCLUDING optional profiles (autogluon, spark, dashboard).
       - run: pip install -e ".[dev,autogluon,spark,dashboard]" pip-licenses