Update aks.bicep

aks.bicep

@@ -1,6 +1,6 @@
 // mandatory params
 @description('The unique DNS prefix for your cluster, such as myakscluster. This cannot be updated once the Managed Cluster has been created.')
-param dnsPrefix string
+param dnsPrefix string = resourceGroup()
 
 @description('The administrator username to use for Linux VMs.')
 param linuxAdminUsername string
@@ -14,10 +14,6 @@ param servicePrincipalClientId string
 @description('The unique name for the AKS cluster, such as myAKSCluster.')
 param uniqueclustername string = resourceGroup()
 
-@secure()
-@description('Unique DNS name.')
-param dnsPrefix string = resourceGroup()
-
 @secure()
 @description('The secret password associated with the service principal.')
 param servicePrincipalClientSecret string