terragrunt validate - issues with root terragrunt.hcl

Failures in root terragrunt.hcl terragrunt validate.
Consider the following dir structure

```
├── dev
│   └── eu-west-1
│   └── project
│   └── terragrunt.hcl
└── terragrunt.hcl
└── common.hcl
```

Where the child includes the parent via `find_in_parent_folders()`.

If the parent has many `read_terraform_config(find_in_parent_folders("common.hcl"))` type includes it will fail when terragrunt validate runs against it in singular. As the dir traversal fails to find the file.

Anything that can be done about this?