Update create-notification-hub-azure-cli.md

In Line 103 and 111, while creating hub with latest version of CLI command we get error:
az notification-hub create --resource-group spnhubrg --namespace-name spnhubns --name spfcmtutorial1nhub --location eastus --sku Free

Error:
unrecognized arguments: --sku Free


Correct command: az notification-hub create --resource-group spnhubrg --namespace-name spnhubns --name spfcmtutorial1nhub --location eastus

Author: khan-mk56

articles/notification-hubs/create-notification-hub-azure-cli.md

@@ -100,15 +100,15 @@ az group create --name spnhubrg --location eastus
    One or more notification hubs can now be created in your new namespace. Run the [az notification-hub create](/cli/azure/notification-hub#az-notification-hub-create) command to create a notification hub.
 
    ```azurecli
-   az notification-hub create --resource-group spnhubrg --namespace-name spnhubns --name spfcmtutorial1nhub --location eastus --sku Free
+   az notification-hub create --resource-group spnhubrg --namespace-name spnhubns --name spfcmtutorial1nhub --location eastus
    ```
 
 2. Create a second notification hub.
 
    Multiple notification hubs can be created in a single namespace. To create a second notification hub in the same namespace, run the `az notification-hub create` command again using a different hub name.
 
    ```azurecli
-   az notification-hub create --resource-group spnhubrg --namespace-name spnhubns --name mysecondnhub --location eastus --sku Free
+   az notification-hub create --resource-group spnhubrg --namespace-name spnhubns --name mysecondnhub --location eastus 
    ```
 
 3. Get a list of notification hubs.