Fixed a typo in DataLoaderTest

Author: lordthorzonus

tests/Unit/DataLoaderTest.php

@@ -889,7 +889,7 @@ function ($keys) {
 
                 return resolve(
                     \array_map(
-                        fn($key) => ($key % 2 === 0) ? $key : new \Exception("Odd: {$key}");
+                        fn($key) => ($key % 2 === 0) ? $key : new \Exception("Odd: {$key}"),
                         $keys
                     )
                 );