Add role="presentation" to .course-wrapper to prevent table

lms/templates/courseware/courseware.html

@@ -161,10 +161,10 @@ ${fragment.foot_html()}
 % endif
 
 <div class="container">
-  <div class="course-wrapper">
+  <div class="course-wrapper" role="presentation">
 
 % if disable_accordion is UNDEFINED or not disable_accordion:
-    <div class="course-index" role="navigation">
+    <div class="course-index">
       <header id="open_close_accordion">
         <a href="#">${_("close")}</a>
       </header>