Add ability to detect changes caused by updates in the include files

[oioki]

For example, such change in terragrunt/_includes/st-customer-module.hcl:

terraform {
-  source = "[email protected]:getsentry/terraform-modules//single-tenant/customer?ref=oldref"
+  source = "[email protected]:getsentry/terraform-modules//single-tenant/customer?ref=newref"
}

Would be nice if tacos would detect whatever uses this include file, in this case, all ST environments. Maybe we can grep on _includes/st-customer-module.hcl