v1.3.5: Fix GitHub Actions build (4)

.github/workflows/build.yml

@@ -7,6 +7,9 @@ jobs:
   prepare:
     name: Prepare Data
     id: prepare
+    steps:
+    - uses: actions/checkout@v2
+    - name: Prepare environment variables
       run: |
         echo ::set-output name=SOURCE_NAME::${GITHUB_REF#refs/*/}
         echo ::set-output name=SOURCE_BRANCH::${GITHUB_REF#refs/heads/}
@@ -16,6 +19,7 @@ jobs:
     name: GitHub Package Registry
     id: ghpr
     runs-on: ubuntu-latest
+    needs: [prepare]
     env:
       SOURCE_NAME: ${{ steps.prepare.outputs.SOURCE_NAME }}
       SOURCE_BRANCH: ${{ steps.prepare.outputs.SOURCE_BRANCH }}