Merge pull request #268364 from ManoharLakkoju-MSFT/patch-115

(AzureCXP) fixes MicrosoftDocs/azure-docs#120478

Author: prmerger-automator[bot]

articles/application-gateway/ingress-controller-letsencrypt-certificate-application-gateway.md

@@ -95,7 +95,7 @@ Use the following steps to install [cert-manager](https://docs.cert-manager.io)
         solvers:
           - http01:
                ingress:
-                  class: azure/application-gateway
+                  ingressclassName: azure/application-gateway
     EOF
     ```