Code improvements

app/Middleware/AdminRoleMiddleware.php

@@ -10,7 +10,7 @@ class AdminRoleMiddleware
 {
     public function handle($request, Closure $next)
     {
-        if (!auth()->check()) {
+        if (currentUser() === null) {
             return redirect('/login')->with('message', 'Du musst eingeloggt sein.');
         }