Add an example of sql security alert policy (#241)

* add example of sql security alert policy

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Co-authored-by: Nanxuan Xu <nanxu@microsoft.com>

quickstart/101-sql-security-alert-policy/providers.tf

@@ -0,0 +1,16 @@
+terraform {
+  required_version = ">=1.0"
+  required_providers {
+    azurerm = {
+      source  = "hashicorp/azurerm"
+      version = "~>3.0"
+    }
+    random = {
+      source  = "hashicorp/random"
+      version = "~>3.0"
+    }
+  }
+}
+provider "azurerm" {
+  features {}
+}