Posts, Post Types: Remove / from non-self-closing "clear" div tags.

In [49178], self-closing `br` tags were switched to non-self-closing `div` elements for "clearing" purposes, but the self-closing "/" remained in place.  This fix removes the unnecessary slash.

Props pavelvisualcomposer, audrasjb, sabernhardt, akabarikalpesh, SergeyBiryukov.
Fixes #52878.

git-svn-id: https://develop.svn.wordpress.org/trunk@50582 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/users.php

@@ -649,7 +649,7 @@ if ( strlen( $usersearch ) ) {
 		<?php $wp_list_table->display(); ?>
 </form>
 
-<div class="clear" /></div>
+<div class="clear"></div>
 </div>
 		<?php
 		break;