Support for aria-keyshortcuts

[nadeemc]

Hi!

Is there a plan to bring aria-keyshortcuts support to the link hint text? This would allow web developers to make clickable elements more consistently have the same key...or the same prefix, in the case where an aria-keyshortcuts value is used more than once.

I didn't see this mentioned in any other issues. Want to make sure it is not purposefully excluded before attempting a PR.