Created by: cpsievert
Fully closes #33625 (closed) (follow up to #33626)
This adds support for .dropdown-items to be wrapped in <li> tags which is the HTML structure that the docs currently recommend.
It'd be great to backport this fix to BS4 as well since that suffers from the same problem, which is a pretty unfortunate change from BS3 (which required <a> tags to be wrapped in <li>)