Mapping <s> element to role=deletion #466

Follows on from w3c/html-aam#416 (w3c/html-aam#442) and w3c/aria#1834

There has been prior agreement in html-aam WG for the nominative change to update the mapping of the <s> element to role=deletion, with a corresponding update to the deletion role description in aria to enable this change.

Filing this for consideration to make the equivalent changes to the html-aria spec for the role mapping definition of the <s> element for consistency - moving from "no corresponding role" to "deletion".

Pertinent areas:

• html-aria/index.html

  Line 2616 in 4d9fc05

  <a>No corresponding role</a>

• https://w3c.github.io/html-aria/#docconformance