Fix missing class on RelationshipsWithIncludes

Author: d8vjork

src/Http/Resources/RelationshipsWithIncludes.php

@@ -4,6 +4,7 @@
 
 use Illuminate\Database\Eloquent\{Model, Collection};
 use Illuminate\Pagination\LengthAwarePaginator;
+use Illuminate\Support\Arr;
 
 /**
  * @property mixed $resource