HTML Guide for listitem
A <li> element is used to define an item of a list, so adding the listitem role to it is redundant.
The ARIA listitem role can be used to identify an item inside a list of items. It is normally used in conjunction with the list role, which is used to identify a list container.
<section role="list">
<div role="listitem">List item 1</div>
<div role="listitem">List item 2</div>
<div role="listitem">List item 3</div>
</section>
When possible, you should use the appropriate semantic HTML elements to mark up a list and its list items — <ul> or <ol>, and <li>. For example:
<ul>
<li>List item 1</li>
<li>List item 2</li>
<li>List item 3</li>
</ul>