code: func (fts *FargateTaskState) MarshalJSON() ([]byte, error) {
  	return fts.BaseTask.marshalMergedParams("arn:aws:states:::ecs:runTask.sync",
  		&fts.parameters)
  }
docs: // MarshalJSON for custom marshalling, since this will be stringified and we need it
  // to turn into a stringified Ref:
  // https://docs.aws.amazon.com/step-functions/latest/dg/connectors-ecs.html