Terragrunt and tflint warnings "Variable declared but not used"

Question

I use Terraform and Terragrunt.

I use inputs field in terragrunt.hcl file from where I also call a local module:

include "root" {
  path = find_in_parent_folders()
}

terraform {
  source = "../../modules/dns"
}

inputs = {
  dns_zone_id = "1234"
}

But it seems that I also must declare variables.tf file:

variable "dns_zone_id" {
  description = "Cloudflare DNS zone ID"
  type        = string
}

If I do not declare variables.tf file I get errors when running terragrunt plan:

An input variable with the name "dns_zone_id" has not been
│ declared. This variable can be declared with a variable
│ "dns_zone_id" {} block.

But the problem is that tflint complains and does not understand that variables is used in inputs block in terragrunt.hcl file:

Is there any workaround for this issue besides using tflint ignore? Am i missing something in terragrunt? I do not see in terragrunt docs that they use variables.tf. Best regards