Changed the method of defining subnets in the main module.

main.tf

@@ -18,13 +18,7 @@ module "network" {
   source = "./modules/network"
 
   name = var.network_name
-  subnets = [
-    {
-      name   = var.subnet_name
-      region = var.region
-      cidr   = var.subnet_cidr
-    }
-  ]
+  subnets = var.subnets
 }
 
 module "vm" {
@@ -32,7 +26,7 @@ module "vm" {
 
   name         = "vm-test"
   network_name = var.network_name
-  subnet_name  = var.subnet_name
+  subnet_name  = var.subnets[0].name
   ssh          = var.ssh
 
   depends_on = [module.network]