CalendarNavigation: use current date as default date in calendar URLs, fixes #3847

Closes #3847

Merge request studip/studip!2729

lib/navigation/CalendarNavigation.php

@@ -21,7 +21,7 @@ class CalendarNavigation extends Navigation
     public function __construct()
     {
         $title = _('Kalender');
-        $main_url = URLHelper::getURL('dispatch.php/calendar/calendar');
+        $main_url = URLHelper::getURL('dispatch.php/calendar/calendar', ['defaultDate' => date('Y-m-d')]);
         if (!$GLOBALS['perm']->have_perm('admin') && Config::get()->SCHEDULE_ENABLE) {
             $title = _('Stundenplan');
             $main_url = URLHelper::getURL('dispatch.php/calendar/schedule');
@@ -47,7 +47,7 @@ class CalendarNavigation extends Navigation
         }
 
         if (Config::get()->CALENDAR_ENABLE) {
-            $navigation = new Navigation(_('Kalender'), 'dispatch.php/calendar/calendar');
+            $navigation = new Navigation(_('Kalender'), 'dispatch.php/calendar/calendar', ['defaultDate' => date('Y-m-d')]);
             $this->addSubNavigation('calendar', $navigation);
         }
     }