fix: add form serialized data to the delete comment ajax form submit

Even if in fresh Plone there is no data, I'm in a case where I'm adding
'ajax' marker in the form to not render all the page (which is the case
here) and the render is not used at all except if the action do not
happens in ajax.

plone/app/discussion/browser/javascripts/comments.js

@@ -177,6 +177,7 @@
             $.ajax({
                 type: 'POST',
                 url: form_url,
+                data: data,
                 context: $(trigger).parents(".comment"),
                 success: function (data) {
                     var comment = $(this);