[Autocomplete] Add a way to translate "Loading more results"

[lukepass]

Hello, as per title it could be useful to customize the "Loading more results" message that appears when scrolling down the select.

Thanks.

[weaverryan]

Yea, it looks like under render - https://github.com/symfony/ux/blob/2.x/src/Autocomplete/assets/src/controller.ts#L220 - we need to specify the loading_more from https://tom-select.js.org/plugins/virtual_scroll/ - set it to a value that can be passed in. PR welcome :)