How to add editor-style.css to the toolbox theme

I’m working on a child theme for Toolbox, I would like to add the editor-style.css to the child theme but the Toolbox theme doesn’t seem to use it.

Can anyone tell me how to update the functions.php in my child theme to allow the editor-style.css to work.

Thanks.

https://www.ads-software.com/extend/themes/toolbox/