Update doc

Author: michaelkad

website/docs/d/pi_network.html.markdown

@@ -41,7 +41,7 @@ Review the argument references that you can specify for your data source.
 
 - `pi_cloud_instance_id` - (Required, String) The GUID of the service instance associated with an account.
 - `pi_network_id` - (Optional, String) The network ID.
-- `pi_network_name` - (Deprecated, Optional, String) The name of the network. Please use `pi_network_id` instead.
+- `pi_network_name` - (Deprecated, Optional, String) The unique identifier or name of the network. Passing the name of the instance could fail or fetch stale data. Please pass an id and use `pi_network_id` instead.
 
 ## Attribute Reference