Fix EC2 example+templates' hashicups module path

[jjti]

This fixes the EC2 templates hashicups module path. It's missing that extra / before modules.

This shouldn't require a version bump, because nothing in main or /modules changed, only the example + template

Testing

Ran make to generate the changes in the PR

Changed the UI template to use us-east-1 and ran TF apply:

locals {
  vpc_region       = "us-east-1"
  hvn_region       = "us-east-1"
  cluster_id       = "test-module-path-fix"
  hvn_id           = "test-module-path-fix-hvn"
  install_demo_app = true
  ssm              = true
}