Add update-link-index action step

Author: reakaleek

.github/workflows/preview-build.yml

@@ -138,13 +138,18 @@ jobs:
         if: steps.deployment.outputs.result
 
       - name: Upload to S3
+        id: s3-upload
         if: steps.deployment.outputs.result
         run: |
           aws s3 sync .artifacts/docs/html "s3://elastic-docs-v3-website-preview${PATH_PREFIX}" --delete
           aws cloudfront create-invalidation \
             --distribution-id EKT7LT5PM8RKS \
             --paths "${PATH_PREFIX}" "${PATH_PREFIX}/*"
 
+      - name: Update Link Index
+        if: steps.s3-upload.outcome == 'success'
+        uses: elastic/docs-builder/actions/update-link-index@main
+
       - name: Update deployment status
         uses: actions/github-script@v7
         if: always() && steps.deployment.outputs.result