Update role allowances for section element to include group

[scottaohara]

ARIA in HTML is updating the <section> element to allow authors to specify role=group.

w3c/html-aria#367

[tombrunet]

Referenced issue is still open. Sandbox testcase for when it's ready: https://codesandbox.io/s/issue-528-ktuyg

[scottaohara]

@tombrunet the referenced issue / PR is opened as we are pushing changes based on implementation commitment. If you were to indicate commitment, then we would have 2 implementations needed to merge.

[tombrunet]

PR: #561

[scottaohara]

Thank you much!

[tombrunet]

Deploying to preview. Should be there in about 30 mins