Document NLK creation via Terraform

terraform/extensions/nlk/main.tf

@@ -0,0 +1,33 @@
+terraform {
+  required_version = "~> 1.3"
+  required_providers {
+    azurerm = {
+      source  = "hashicorp/azurerm"
+      version = "~> 3.97"
+    }
+  }
+}
+
+provider "azurerm" {
+  features {}
+}
+
+resource "azurerm_kubernetes_cluster_extension" "nlk" {
+  name           = "test-ext"
+  # fill out cluster ID.
+  cluster_id     = "/subscriptions/ee920d60-90f3-4a92-b5e7-bb284c3a6ce2/resourceGroups/testenv-900d48c0-aks-resources/providers/Microsoft.ContainerService/managedClusters/testenv-900d48c0-aks"
+  extension_type = "nginxinc.nginxaas-aks-extension"
+  release_namespace = "nlk"
+  # release_train will be "Stable" after publishing the offer.
+  release_train = "Preview"
+  plan {
+    name = "f5-nginx-for-azure-aks-extension"
+    product = "f5-nginx-for-azure-aks-extension"
+    publisher = "f5-networks"
+  }
+
+  configuration_settings = {
+    "nlk.dataplaneApiKey" = "testmyKey123456!"
+    "nlk.config.nginxHosts" = "https://nlkdemo-d81e16277aa1.westcentralus.nginxaas.net/nplus"
+  }
+}