ncc: add descriptions for preset_topology and policy_mode

Author: paulwilljones

examples/network_connectivity_center/main.tf

@@ -18,6 +18,7 @@ module "network_connectivity_center" {
   source  = "terraform-google-modules/network/google//modules/network-connectivity-center"
   version = "~> 13.0"
 
+
   project_id   = var.project_id
   ncc_hub_name = var.ncc_hub_name
   ncc_hub_labels = {

examples/network_connectivity_center/versions.tf

@@ -36,13 +36,13 @@ variable "ncc_hub_labels" {
 }
 
 variable "ncc_hub_preset_topology" {
-  description = "The topology implemented in the hub"
+  description = "The topology implemented in the hub. Type must be one of `STAR` or `MESH`."
   type        = string
   default     = null
 }
 
 variable "ncc_hub_policy_mode" {
-  description = "The policy mode of the hub"
+  description = "The policy mode of the hub. Type must be one of `PRESET` or `CUSTOM`."
   type        = string
   default     = "PRESET"
 }