deleteListItemElement(start, end) {
    const { items } = this;

    for (let i = start; i < end; i += 1) {
      this.listElement.removeChild(items[i]);
    }
    items.splice(start, end - start + 1);
  }
Delete list item element
@param {number} start - start index to delete
@param {number} end - end index to delete