Remove creation of infra_rg variable

Not required after 63caa97.

Author: JatinSanghvi

articles/app-service/manage-create-arc-environment.md

@@ -66,7 +66,6 @@ az extension add --upgrade --yes --name appservice-kube
 
     az group create -g $aksClusterGroupName -l $resourceLocation
     az aks create --resource-group $aksClusterGroupName --name $aksName --enable-aad --generate-ssh-keys
-    infra_rg=$(az aks show --resource-group $aksClusterGroupName --name $aksName --output tsv --query nodeResourceGroup)
     ```
 
     # [PowerShell](#tab/powershell)