Ensure correct URL for the refresh container button

Shifted params no longer appear in the URL which is retrieved from the request object.
We now use Url::fromRequest() instead.

library/Icinga/Web/Widget/Tabs.php

@@ -315,7 +315,7 @@ EOT;
 
     private function renderRefreshTab()
     {
-        $url = Icinga::app()->getRequest()->getUrl();
+        $url = Url::fromRequest();
         $tab = $this->get($this->getActiveName());
 
         if ($tab !== null) {