[DOCS]: Listbox states that "Enter" on button will open the listbox

[JakeDluhy]

Not sure if this is a bug or a docs issue, but the docs for the Listbox in v2 state that "Enter" will open the Listbox, but I was not finding that to be the case in my application. Looking at the code it looks like that is not the case in the code either: https://github.com/tailwindlabs/headlessui/blob/main/packages/%40headlessui-react/src/components/listbox/listbox.tsx#L763

So I think the docs need to be updated?