Display Posts outputs an unordered list (<ul>) by default, but you can change this to an ordered list or div using If you would prefer a different wrapping element, like a <section>, you can use the following:
Filter: display_posts_shortcode_wrapper_open
Customize the outer opening markup for the entire listing. By default it is ul but can be changed to ol or div using the ‘wrapper’ attribute. Use this filter to change it to any HTML element.