Only download the context when contracts are deployed

.github/workflows/deploy-testnet.yml

@@ -2,6 +2,7 @@ name: Deploy the contracts + app
 env:
  VERCEL_ORG_ID: ${{ secrets.VERCEL_ORG_ID }}
  VERCEL_PROJECT_ID: ${{ secrets.VERCEL_PROJECT_ID }}
+ DEPLOY_CONTRACTS: 'no'
 on:
  push:
  branches: [deploy-contracts-and-app]
@@ -20,8 +21,8 @@ concurrency:
 
 jobs:
  deploy-contracts:
- if: false
  name: Deploy contracts to the Liquity v2 Testnet
+ if: ${{ env.DEPLOY_CONTRACTS != 'no' }}
  runs-on: ubuntu-latest
  steps:
  - name: Git checkout
@@ -78,6 +79,7 @@ jobs:
  run: pnpm install --global vercel@canary
 
  - name: Download deployment context
+ if: ${{ env.DEPLOY_CONTRACTS != 'no' }}
  uses: actions/download-artifact@v4
  with:
  name: deployment-context