Adds NAT GW for vpc-scanners

prod/aws-us-gov/mdr-prod-c2/010-vpc-scanners/terragrunt.hcl

@@ -39,6 +39,7 @@ inputs = {
     Purpose = "Vulnerability Scanners"
     Terraform = "aws/${basename(get_parent_terragrunt_dir())}/${path_relative_to_include()}/"
   }
+  enable_nat_gateway = true  #needed for Nessus scanners to scan customer portal.
 }
 terraform_version_constraint = "= 0.15.1"
 terragrunt_version_constraint = ">= 0.29, < 0.30"