TCLOUD-4894: add stale-if-error (#3982)

Author: tiny-mcg

.github/workflows/deploy_docs_v2.yml

@@ -69,11 +69,11 @@ jobs:
       run: |
         aws s3 sync ./build s3://${BUCKET}/main/${RUN} \
           --exclude "*/index.html" \
-          --cache-control "public, max-age=3600, stale-while-revalidate=86400"
+          --cache-control "public, max-age=3600, stale-if-error=3600, stale-while-revalidate=86400"
         aws s3 sync ./build s3://${BUCKET}/main/${RUN} \
           --exclude "*" \
           --include "*/index.html" \
-          --cache-control "max-age=300, stale-while-revalidate=86400"
+          --cache-control "max-age=300, stale-if-error=3600, stale-while-revalidate=86400"
 
     - name: Create redirects on S3
       uses: tinymce/tinymce-docs-generate-redirects-action@v1.0