First parameter of `assign` in SQLUpdate not escaped

[NoLdman]

In

sortablefile/src/Forms/SortableUploadField.php

Line 199 in 0028923

->assign($sortColumn, $sort++)

the first parameter of assign isn't escaped, which causes SilverStripe-Installations with PostgreSQL databases to cast the column to lower-case (i.e. "sortorder").

Shouldn't it be escaped as follows?

->assign("\"$sortColumn\"", $sort++)