Fix cesium.com branch for real I swear

We don't actually build the zip in cesium.com deploy,
we fetch it from GH releases. That's the root cause
of why unzipping was failing.

.github/workflows/prod.yml

@@ -46,6 +46,7 @@ jobs:
       - name: deploy to cesium.com
         if: ${{ env.AWS_ACCESS_KEY_ID != '' }}
         run: |
+          curl -LO $(curl https://api.github.com/repos/CesiumGS/cesium/releases/latest -H "Authorization: ${GITHUB_TOKEN}" | jq -r '.assets[0].browser_download_url')
           unzip Cesium-$(cat package.json | jq -r '.version' | sed 's/\.0$//').zip -d Build/release/ -x "Apps"
           aws s3 sync Build/release/ s3://cesium-website/cesiumjs/releases/$(cat package.json | jq -r '.version' | sed 's/\.0$//')/ --cache-control "public, max-age=1800" --delete
           aws s3 sync Build/Documentation/ s3://cesium-website/cesiumjs/ref-doc/ --cache-control "public, max-age=1800" --delete