async getItem(itemPosition) {
        const items = await $(this.rootElement).$$('li[role="presentation"]');
        if (items[itemPosition]) {
            return new PageTab(
                `${this.rootElement} li[role="presentation"]:nth-child(${itemPosition + 1})`,
            );
        }
        return null;
    }
Returns a new Tab page object of the element in item position.
@method
@param {number} itemPosition - The base 0 index of the tab item.