Remove the go to top button

It’s not particularly useful when there are fixed elements all over the
page (header, sidebar)

ember/app/components/application/go-to-top.js

@@ -1,12 +0,0 @@
-import Ember from 'ember';
-
-import ActionButton from 'flarum/components/ui/action-button';
-
-export default ActionButton.extend({
-  title: 'Go to Top',
-  icon: 'arrow-up',
-  className: 'control-top',
-  action: function() {
-    $('html, body').stop(true).animate({scrollTop: 0});
-  }
-})