put setting into it's own OptionsWidget, re #3109

Merge request studip/studip!2105

app/controllers/calendar/calendar.php

@@ -101,6 +101,7 @@ class Calendar_CalendarController extends AuthenticatedController
         $tmpl->action_url = $this->url_for();
         $tmpl->category = $this->category;
         $filters->addElement(new WidgetElement($tmpl->render()));
+        Sidebar::get()->addWidget($filters);
 
         if (Config::get()->CALENDAR_GROUP_ENABLE
                 || Config::get()->COURSE_CALENDAR_ENABLE) {
@@ -109,14 +110,16 @@ class Calendar_CalendarController extends AuthenticatedController
             $tmpl->action_url = $this->url_for('calendar/group/switch');
             $tmpl->view = $this->action;
             $filters->addElement(new WidgetElement($tmpl->render()));
-            $filters->addCheckbox(
+
+            $settings = new OptionsWidget();
+            $settings->addCheckbox(
                 _('Abgelehnte Termine anzeigen'),
                 $this->settings['show_declined'] ?? false,
                 $this->url_for($this->base . 'show_declined', ['show_declined' => 1]),
                 $this->url_for($this->base . 'show_declined', ['show_declined' => 0])
             );
+            Sidebar::get()->addWidget($settings);
         }
-        Sidebar::get()->addWidget($filters);
     }
 
     public function index_action()