Add different solutions to AWS exercises

Not only console solutions, but also Terraform and Pulumi.

In addition, this change fixes issues #279 and #280

topics/aws/exercises/subnets/terraform/main.tf

@@ -0,0 +1,49 @@
+# Variables
+
+variable "vpc_id" {
+  type = string
+}
+
+# AWS Subnets
+
+resource "aws_subnet" "NewSubnet1" {
+  cidr_block = "10.0.0.0/24"
+  vpc_id = var.vpc_id
+  availability_zone = data.aws_availability_zones.all.names[0]
+  tags = {
+    Purpose: exercise
+    Name: "NewSubnet1"
+  }
+}
+
+resource "aws_subnet" "NewSubnet2" {
+  cidr_block = "10.0.1.0/24"
+  vpc_id = var.vpc_id
+  availability_zone = data.aws_availability_zones.all.names[1]
+  tags = {
+    Purpose: exercise
+    Name: "NewSubnet2"
+  }
+}
+
+resource "aws_subnet" "NewSubnet3" {
+  cidr_block = "10.0.2.0/24"
+  vpc_id = var.vpc_id
+  availability_zone = data.aws_availability_zones.all.names[2]
+  tags = {
+    Purpose: exercise
+    Name: "NewSubnet3"
+  }
+}
+
+# Outputs
+
+output "NewSubnet1-id" {
+  value = aws_subnet.NewSubnet1.id
+}
+output "NewSubnet2-id" {
+  value = aws_subnet.NewSubnet2.id
+}
+output "NewSubnet3-id" {
+  value = aws_subnet.NewSubnet3.id
+}