most likely it wont be added to the plugin.. but if you are familiar with PHP here is some tips so you can do it on your own (as it should be quite easy to do since steam use openid) :
1. open wordpress-social-login\hybridauth\Hybrid\Providers\AOL.php
2. find and replace
var $openidIdentifier = "https://openid.aol.com/";
by
var $openidIdentifier = "https://steamcommunity.com/openid/id/";
3. activate AOL from “Providers setup” tabs and then try to connect with (you will be redirected to steam website for authentication instead)