code: func NewWorkItemCreated(workitemID string, revisionID uuid.UUID) Message {
  	return Message{
  		MessageID:   uuid.NewV4(),
  		MessageType: "workitem.create",
  		TargetID:    workitemID,
  		Custom:      map[string]interface{}{"revision_id": revisionID},
  	}
  }
docs: // NewWorkItemCreated creates a new message instance for the newly created WorkItemID