Upgrade GitHub Actions

.github/workflows/python-package.yml

@@ -1,40 +1,36 b''
 # This workflow will install Python dependencies, run tests and lint with a variety of Python versions
 # For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions
 
 name: Python package
 
 on:
   push:
     branches: [ main, 7.x ]
   pull_request:
     branches: [ main, 7.x ]
 
 jobs:
   formatting:
 
     runs-on: ubuntu-latest
     timeout-minutes: 5
-    strategy:
-      matrix:
-        python-version: [3.8]
-
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
       with:
         fetch-depth: 0
-    - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v2
+    - name: Set up Python
+      uses: actions/setup-python@v4
       with:
-        python-version: ${{ matrix.python-version }}
+        python-version: 3.x
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
         pip install darker black==21.12b0
     - name: Lint with darker
       run: |
         darker -r 60625f241f298b5039cb2debc365db38aa7bb522 --check --diff . || (
         echo "Changes need auto-formatting. Run:"
         echo "    darker -r 60625f241f298b5039cb2debc365db38aa7bb522"
         echo "then commit and push changes to fix."
         exit 1
         )