Replace <i> tags with <span>s.

The i tag is for italic and should not be used for icons.

drag_and_drop_v2/public/js/drag_and_drop.js

@@ -8,7 +8,7 @@ function DragAndDropTemplates(configuration) {
         }
         return (
             h("div.spinner-wrapper", {key: item.value + '-spinner'}, [
-                h("i.fa.fa-spin.fa-spinner")
+                h("span.fa.fa-spin.fa-spinner")
             ])
         );
     };

drag_and_drop_v2/templates/html/drag_and_drop.html

 {% load i18n %}
 <div class="themed-xblock xblock--drag-and-drop">
-    <i class="fa fa-spin fa-spinner initial-load-spinner"></i>{% trans "Loading drag and drop problem." %}
+    <span class="fa fa-spin fa-spinner initial-load-spinner"></span>{% trans "Loading drag and drop problem." %}
 </div>