Merge pull request statsmodels#8500 from statsmodels/dependabot/github_actions/actions/setup-python-4

Bump actions/setup-python from 3 to 4

Author: bashtage

.github/workflows/generate-documentation.yml

@@ -52,7 +52,7 @@ jobs:
     - name: Install graphviz
       uses: ts-graphviz/setup-graphviz@v1
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v3
+      uses: actions/setup-python@v4
       with:
         python-version: ${{ matrix.python-version }}
         cache: "pip"