Terraform: Docker provider does not respect insecure-registries?

I am trying to pull a Docker image from a local Artifactory when the digest of the image changed. But I am confused about Terrform configuration and its relation to the installed Docker Desktop.

The Terrform script starts with:

terraform {
 required_providers {
  docker = {
    source = "terraform-providers/docker"
  }
 }
}

provider "docker" {
  host = "npipe:////.//pipe//docker_engine"

  registry_auth {
    address= "ip:port"
    username = "my-username"
    password = "my-password"
  }
}

data "docker_registry_image" "my-image" {
  name = "ip:port/repository-name/my-image:version"
}

resource "docker_image" "my-image" {
  name = "my-image-name"
  pull_triggers = ["data.docker_registry_image.my-image.sha256_digest"]
  keep_locally = true
}

I added the registry ip:port to the insecure-registries so that also Terraform has access to it.

The problem is that the insecure-registries from Docker Desktop is somehow ignored by Terraform (Docker provider) because I get the response:

Error: Got error when attempting to fetch image version from registry: Error during registry request: Get https://ip:port/v2/repository-name/my-image:version: http: server gave HTTP response to HTTPS client.

  on script.tf line 20, in data "docker_registry_image" "my-image":
  20: data "docker_registry_image" "my-image" {

Can anyone help? Does somebody know why insecue-registries set in Docker Desktop does not apply here?