fix chunkById for types other than ObjectId and laravel >= 5.6.25 (#1543)

Author: halaei

src/Jenssegers/Mongodb/Query/Builder.php

@@ -633,12 +633,6 @@ public function chunkById($count, callable $callback, $column = '_id', $alias =
      */
     public function forPageAfterId($perPage = 15, $lastId = 0, $column = '_id')
     {
-        // When using ObjectIDs to paginate, we need to use a hex string as the
-        // "minimum" ID rather than the integer zero so the '$lt' query works.
-        if ($column === '_id' && $lastId === 0) {
-            $lastId = '000000000000000000000000';
-        }
-
         return parent::forPageAfterId($perPage, $lastId, $column);
     }