Ensure environment tag is lowercase

Author: nikki-t

terraform/main.tf

@@ -42,7 +42,7 @@ locals {
   account_id = data.aws_caller_identity.current.account_id
   default_tags = length(var.default_tags) == 0 ? {
     application : var.app_name,
-    environment : var.environment,
+    environment : lower(var.environment),
     version : var.app_version
   } : var.default_tags
 }