CCM-10294: use new workflow

Author: mark-r-bjss

.github/workflows/stage-4-acceptance.yaml

@@ -15,6 +15,8 @@ jobs:
       SANDBOX_NAME: ${{ steps.normalize_branch_name.outputs.normalized_branch_name }}
     timeout-minutes: 3
     steps:
+      - name: "Checkout code"
+        uses: actions/checkout@v4
       - name: "Get normalized branch name"
         id: normalize_branch_name
         uses: ./.github/actions/normalize-branch-name