gistfile1.php

<?php

return [
   // ...
   'invokables' => [
        // move your controller declaration from here
   ],
   'factories' => [
        // to here
        'yourController' => function($sl) {
            return new YourController($sl);
        }
   ]
   //...
];


// and in controller class

class YourController extends Controller {
    
    public __construct($sl) {
         $this->userModel = $sl->get('doctrine.entitymanager.orm_default');
    }
    // ...
}