Settings is an argument not a block

Copying the example in the readme, fails with error

```
Error: Unsupported block type
```

Author: Arola1982

website/docs/r/alert_notification.html.md

@@ -20,7 +20,7 @@ resource "grafana_alert_notification" "email_someteam" {
   send_reminder = true
   frequency = "24h"
 
-  settings {
+  settings = {
     addresses = "[email protected];[email protected]"
     uploadImage = "false"
   }