Make 'useSetup' second argument and createSetup argument optional.

[Dave.rs]

Hi, a little thing, If I have a component with no props, then I don't have a prop argument for the useSetup, but typescript is requiring it and I use an empty object instead. And the same for 'createSetup', It is forcing me to give it an empty object or something.

[Anthony Fu]

Make sense. Would you mind to send a PR? Thanks

[Anthony Fu]

Thanks!