docs: Update continuous-deployment.mdx (#9116)

Author: AvilaJulio

docs/pages/product/deployment/cloud/continuous-deployment.mdx

@@ -101,10 +101,12 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@v2
-      - name: Use Node.js 14.x
+      - name: Use Node.js 20.x
         uses: actions/setup-node@v1
         with:
-          node-version: 14.x
+          node-version: 20.x
+      - name: Install Cube backend server core
+        run: npm i @cubejs-backend/server-core
       - name: Deploy to Cube Cloud
         run: npx cubejs-cli deploy --token ${{ secrets.CUBE_CLOUD_DEPLOY_AUTH }}
 ```