Merge pull request #2 from PartTimeLegend/renovate/actions-checkout-4.x

Update actions/checkout action to v4

.github/workflows/documentation.yml

@@ -11,7 +11,7 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       - name: Set up Python
         uses: actions/setup-python@v5