Shouldn’t a target be specified for tsup?

### Discussed in https://github.com/ariakit/ariakit/discussions/2344

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<sup>Originally posted by **MrHBS** May  1, 2023</sup>
I have noticed the project builds without specifying a target for tsup. This basically means it outputs the very latest JS code which may not be widely supported by browsers. Perhaps I am wrong?</div>