code: @UiThread
      @Override
      public void onBindChildViewHolder(@NonNull HorizontalChildViewHolder childViewHolder, int parentPosition,
                                        int childPosition, @NonNull HorizontalChild horizontalChild) {
          childViewHolder.bind(horizontalChild.getChildText());
      }
docs: OnBindViewHolder implementation for child items. Any data or view modifications of the
  child view should be performed here.
  
  @param childViewHolder the ViewHolder of the child item created in OnCreateChildViewHolder
  @param childPosition the position in the RecyclerView of the item