Typecast $column to string when ordering

Author: apeisa

src/Query/Builder.php

@@ -512,7 +512,7 @@ public function orderBy($column, $direction = 'asc')
         if ($column == 'natural') {
             $this->orders['$natural'] = $direction;
         } else {
-            $this->orders[$column] = $direction;
+            $this->orders[(string) $column] = $direction;
         }
 
         return $this;