Update actions/checkout action to v4

| datasource  | package          | from | to |
| ----------- | ---------------- | ---- | -- |
| github-tags | actions/checkout | v2   | v4 |

Author: renovate[bot]

.github/workflows/forms-backend.yml

@@ -13,7 +13,7 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       - name: Install Python Dependencies
         uses: HassanAbouelela/actions/setup-python@setup-python_v1.6.0
@@ -65,7 +65,7 @@ jobs:
           echo "::set-output name=tag::$tag"
 
       - name: Checkout repository
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       - name: Setup Docker BuildX
         uses: docker/setup-buildx-action@v1
@@ -105,7 +105,7 @@ jobs:
           echo "::set-output name=tag::$tag"
 
       - name: Checkout repository
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       - name: Authenticate with Kubernetes
         uses: azure/k8s-set-context@v1