fix for bug with tf

Author: anarwal

module/single-node-omnibus/alb.tf

@@ -4,7 +4,7 @@ resource "aws_lb" "gitlab_alb" {
   internal           = false
   security_groups    = ["${aws_security_group.gitlab_alb.id}"]
   ip_address_type    = "ipv4"
-  subnets            = "${var.public_subnet_id}"
+  subnets            = ["${var.public_subnet_id}"]
   tags               = "${merge (module.gitlab_label.tags, map ("Role", module.gitlab_label.name ))}"
 }
 

module/single-node-omnibus/local-resources.tf

@@ -1,10 +1,10 @@
 # use this resource when a module accepts a subnet id as an input variable and needs to, for example, determine the id of the VPC that the subnet belongs to.
 data "aws_subnet" "private_selected" {
-  id = "${element (var.private_subnet_id, 0)}"
+  id = "${element (["${var.private_subnet_id}"], 0)}"
 }
 
 data "aws_subnet" "public_selected" {
-  id = "${element (var.public_subnet_id, 0)}"
+  id = "${element (["${var.public_subnet_id}"], 0)}"
 }
 
 # Use this data source to get the access to the effective Account ID, User ID, and ARN in which Terraform is authorized.