Dynamic step blocks in Terraform google_cloudbuild_trigger resulting in argument Unsupported errors

I am attempting to dynamically generate blocks within a google_cloudbuild_trigger

resource "google_cloudbuild_trigger" "push_to_production" {
  name = "cloudbuild-workers"
  location = var.region
    build {
      dynamic "step" {  
        for_each    = local.workers
          id        = "deploy-worker-${each.value}"
          name      = "gcr.io/google.com/cloudsdktool/cloud-sdk"
          entrypoint = "gcloud"
          args      = ["run", "services", "update", each.value, "--platform=managed", "--image=$_WORKER_IMG", "--region=$_REGION",  "--quiet"]
    }
  }
}

which should generate a list of build steps in my trigger for each of my worker configurations in local.workers. But what I'm seeing is errors for every attribute.

An argument named "id" is not expected here.

An argument named "name" is not expected here.

An argument named "entrypoint" is not expected here.

An argument named "args" is not expected here.

Is there something wrong with the way this is structured?

When using dynamic block, there also has to be the content, i.e:

resource "google_cloudbuild_trigger" "push_to_production" {
  name = "cloudbuild-workers"
  location = var.region
  build {
    dynamic "step" {  
      for_each = local.workers
      content {
        id         = "deploy-worker-${step.value}"
        name       = "gcr.io/google.com/cloudsdktool/cloud-sdk"
        entrypoint = "gcloud"
        args       = ["run", "services", "update", step.value, "--platform=managed", "--image=$_WORKER_IMG", "--region=$_REGION",  "--quiet"]
      }
    }
  }
}

Additionally, since you are using the dynamic block, the each object is basically swapped for an iterator. The iterator name usually corresponds to the name of the dynamic block if you don't provide the name for it.

However, even if this syntax is now correct, I don't think it will work, since the build block for this resource says that the step block is required.