Update actions/setup-python action to v4

Author: renovate[bot]

.github/workflows/pylint.yml

@@ -10,7 +10,7 @@ jobs:
     steps:
     - uses: actions/checkout@v3
     - name: Set up Python 3.9
-      uses: actions/setup-python@v2
+      uses: actions/setup-python@v4
       with:
         python-version: 3.9
     - name: Install dependencies

.github/workflows/python-app.yml

@@ -17,7 +17,7 @@ jobs:
     steps:
     - uses: actions/checkout@v3
     - name: Set up Python 3.9
-      uses: actions/setup-python@v2
+      uses: actions/setup-python@v4
       with:
         python-version: 3.9
     - name: Install dependencies