An EuiHealth EuiIcon element is "just" a color circle SVG image. For a screen reader user, this will read out as "image" if no aria-label was specified, which is not very helpful at all.

I think we should have a prop type check, that checks that one of the following conditions is true:

• aria-hidden is true
• aria-label was set
• aria-labelledby was set

That way we could ensure, that we never end up with a blank SVG without any label that is still visible to screen readers. Inspired by elastic/kibana#17410