GitHub Actions: update actions.

Author: greenrobot-team

.github/workflows/test.yaml

@@ -15,10 +15,10 @@ jobs:
     runs-on: ${{ matrix.os }}-latest
 
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
 
       - name: Set up Python ${{ matrix.python }}
-        uses: actions/setup-python@v2
+        uses: actions/setup-python@v4
         with:
           python-version: ${{ matrix.python }}
           cache: 'pip'