Fix usage of "new ArrayBuffer" in SHA

Author: twiss

spec/Overview.html

@@ -12970,7 +12970,8 @@ <h4>Operations</h4>
                 </li>
                 <li>
                   <p>
-                    Return a new ArrayBuffer containing |result|.
+                    Return the result of [= ArrayBuffer/create | creating =]
+                    an {{ArrayBuffer}} containing |result|.
                   </p>
                 </li>
               </ol>