Merge pull request #270723 from duongau/patch-8

AFD TOC -  add WAF entry

Author: ttorble

articles/frontdoor/TOC.yml

@@ -18,6 +18,8 @@
           href: ../cdn/cdn-features.md?toc=/azure/frontdoor/TOC.json
   - name: Front Door and CDN comparison
     href: front-door-cdn-comparison.md
+  - name: Well-Architected review of Front Door
+    href: /azure/well-architected/service-guides/azure-front-door
 - name: Quickstarts
   expanded: true
   items: