KIconButton: Set tooltip value as fallback if ariaLabel is missing

[AlexVelezLl]

🌱 Are you new to the codebase? Welcome! Please see the contributing guidelines.

Product

Kolibri, Studio, etc.

Description

In KIconButton we have these two props related but not exactly the same: ariaLabel and tooltip. For accessibility purposes we dont want these props to be the same, but if the user forgot to send an ariaLabel prop but they sent a tooltip prop, the ariaLabel should take the value of the tooltip prop.

This means, the aria label of the icon button will be set by the ariaLabel prop, and have the tooltip value as fallback if ariaLabel is missing.

The Value Add

This will improve accessibility in places where we have tooltips but no aria labels. And in the future we can just send the tooltip prop if we want the ariaLabel to have the same value.