Load get_page_templates into select menu

Reading the documentation:

List of choices for ‘radio’ or ‘select’ type controls, where values are the keys, and labels are the values.

And again for get_page_templates():

Return value: (array) Where key is the name of the template and value is the filename.

Thus we can conclude:

'choices' => array_flip( get_page_templates() ),

Now I’m spoiling you