chore(sparkle): unify button props (always use variant vs type)

[fontanierh]

follow up for #1297, which renamed the type property of Button to variant. For consistency, this commit does the same for IconButton and IconToggleButton

[Duncid]

Thanks, wanted to do that !

[Duncid]

FYI, did it for Buttons in a previous PR.
But I did not change the front code base yet.
If you move the front to the new Sparkle package it will break (but you probably noticed already)

[fontanierh]

FYI, did it for Buttons in a previous PR.
But I did not change the front code base yet.
If you move the front to the new Sparkle package it will break (but you probably noticed already)

Yes already updated front in prod for <Button /> :)