Bump actions/setup-python from 2 to 4

Bumps [actions/setup-python](https://github.com/actions/setup-python) from 2 to 4.
- [Release notes](https://github.com/actions/setup-python/releases)
- [Commits](https://github.com/actions/setup-python/compare/v2...v4)

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

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

.github/workflows/deploy-website.yml

@@ -22,7 +22,7 @@ jobs:
           # cache: yarn
           # cache-dependency-path: '**/yarn.lock'
       - name: setup python
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@v4
         with:
           python-version: "3.8"
       - name: pydoc-markdown install
@@ -58,7 +58,7 @@ jobs:
           # cache: yarn
           # cache-dependency-path: '**/yarn.lock'
       - name: setup python
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@v4
         with:
           python-version: "3.8"
       - name: pydoc-markdown install

.github/workflows/python-package.yml

@@ -21,7 +21,7 @@ jobs:
     steps:
       - uses: actions/checkout@v2
       - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@v4
         with:
           python-version: ${{ matrix.python-version }}
       - name: On mac + python 3.10, install libomp to facilitate lgbm and xgboost install
@@ -85,7 +85,7 @@ jobs:
   #   steps:
   #     - uses: actions/checkout@v2
   #     - name: Setup Python
-  #       uses: actions/setup-python@v2
+  #       uses: actions/setup-python@v4
   #       with:
   #         python-version: '3.8'
   #     - name: Compile documentation