adds missing ID for comments

popover comments was missing the id att-popover-comments.  added with this push

html-aam/index.html

@@ -13339,7 +13339,7 @@ <h4 id="att-popover">`popover`</h4>
               </td>
             </tr>
             <tr>
-              <th>Comments</th>
+              <th id="att-popover-comments">Comments</th>
               <td>
                 <p>User agents MUST NOT expose a details relation between a `popover` and its invoking element under the following conditions:</p>
                 <ul>