add ability to change domain name

debian/main.tf

@@ -13,6 +13,7 @@ module "invariants" {
 module "tf_debian_vm" {
   source                = "git::https://git.pim.kunis.nl/pim/tf-debian-vm.git"
   name                  = var.name
+  domain_name           = var.domain_name
   admin_authorized_keys = coalesce(var.admin_authorized_keys, module.invariants.admin_authorized_keys)
   insecure_password     = var.insecure_password
   use_host_cert         = var.use_host_cert

debian/variables.tf

@@ -2,6 +2,11 @@ variable "name" {
   type = string
 }
 
+variable "domain_name" {
+  type = string
+  default = null
+}
+
 variable "admin_authorized_keys" {
   type    = list(string)
   default = null