Fixed accidental $next in conditional statement.

$next($request) shouldn’t be conditional, otherwise the response will
be blank.

src/Http/Middleware/ApiGuard.php

@@ -207,8 +207,7 @@ public function handle($request, Closure $next, $serializedApiMethods=null)
 
         if($user_id !== 0)
             Auth::loginUsingId($user_id);
-
-        return $next($request);
         }
+        return $next($request);
     }
 }