Remove jQuery dependency in favour of vanilla JS

[roborourke]

Not sure if it matters if WooCommerce queues up jQuery on all pages anyway but the event handling could be easily swapped out for vanilla JS. This will mean better performance on sites that otherwise wouldn't need to load jQuery, at least not on all pages.

[vladkononov]

Hi @roborourke, there were never any complaints about it, we will internally discuss this and potentially add this to a backlog, but as a low-priority task. Thank you for the suggestion!