Adding platform option in docker-build module

[GonzalezAndrew]

Is your request related to a new offering from AWS?

Is this functionality available in the AWS provider for Terraform? See CHANGELOG.md, too.

• No 🛑: This feature request is related to the docker provider version 2.22.0.

Is your request related to a problem? Please describe.

When building on M1 Mac, the option to build docker images in other platforms would be a nice feature. Currently when using the docker-build module, the default platform on M1 Mac will be arm but I would like to build x86_64 architecture.

Describe the solution you'd like.

Change the docker_registry_image block in docker-build module to include platform argument:

resource "docker_registry_image" "this" {
  name = local.ecr_image_name

  build {
    context    = var.source_path
    dockerfile = var.docker_file_path
    build_args = var.build_args
    platform = var.platform
  }

  keep_remotely = var.keep_remotely
}

Describe alternatives you've considered.

Setting the AWS Lambda architecture to arm64.

Additional context