CI: Update checkout/setup-python actions for flake8

Author: effigies

.github/workflows/pythonpackage.yml

@@ -102,9 +102,9 @@ jobs:
     if: "!contains(github.event.head_commit.message, '[skip ci]')"
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - name: Set up Python 3.7
-      uses: actions/setup-python@v1
+      uses: actions/setup-python@v3
       with:
         python-version: 3.7
     - run: pip install flake8