add missing <code> within docs heading for `.modal('handleUpdate')`

docs/_includes/js/modal.html

@@ -476,7 +476,7 @@ $('#myModal').modal({
   <p>Manually hides a modal. <strong>Returns to the caller before the modal has actually been hidden</strong> (i.e. before the <code>hidden.bs.modal</code> event occurs).</p>
   {% highlight js %}$('#myModal').modal('hide'){% endhighlight %}
 
-  <h4>.modal('handleUpdate')</h4>
+  <h4><code>.modal('handleUpdate')</code></h4>
   <p>Readjusts the modal's positioning to counter a scrollbar in case one should appear, which would make the modal jump to the left.</p>
   <p>Only needed when the height of the modal changes while it is open.</p>
   {% highlight js %}$('#myModal').modal('handleUpdate'){% endhighlight %}