Moving cosmosdb quickstart code to samples repo

quickstart/101-cosmos-db-azure-container-instance/variables.tf

@@ -0,0 +1,9 @@
+variable "resource_group_location" {
+  default     = "eastus"
+  description = "Location of the resource group."
+}
+
+variable "resource_group_name_prefix" {
+  default     = "rg"
+  description = "Prefix of the resource group name that's combined with a random ID so name is unique in your Azure subscription."
+}