fix: make file input accessible via keyboard

[asimpson]

closes #8

[CLAassistant]

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[yaelleC]

🚀 LGTM
Makes me wonder why we have a LinkButton component at all 🤷‍♀️ 😄 ?
But maybe it's only not accessible because missing an src prop or something like that.

In any case, for the JWT a11y issue your fix works best 👍

[asimpson]

@yaelleC There could be scenarios where LinkButton makes sense? I can't think of one right now. I think a button is better here because links are typically used to signal that an action would navigate you somewhere. A button indicates something is happening on the current page.