Merge pull request #4 from edward3h/renovate/actions-checkout-4.x

Update actions/checkout action to v4

.github/workflows/docker-push.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
       - name: setup buildx
         uses: docker/setup-buildx-action@v1
       - name: docker meta