Merge pull request #72360 from sethmanheim/toc-fix

Fixing incorrect TOC entry

Author: ktoliver

articles/azure-stack/TOC.yml

@@ -403,4 +403,4 @@
   - name: Stack Overflow
     href: https://stackoverflow.com/questions/tagged/azure-stack
   - name: Training and certification
-    href: https://docs.microsoft.com/azure/azure-stack/azure-stack-train-and-cert
+    href: azure-stack-train-and-cert.md