IconButton incorrectly passes aria-label through to its span element

Summary: IconButton incorrectly passes its aria-label prop through to a <span> element it creates, an a11y violation.

Details: IconButton accepts both aria-label and ariaLabel props. The former is passed straight through to a <span> while the latter is siphoned off, correctly, via props destructuring.

Both props should be siphoned off.

Attn: Denys Bohdan, JohnC