Fix autofocus behavior for radio button and check box groups

[camertron]

What are you trying to accomplish?

This PR fixes autofocus behavior for radio button and check box groups. According to Primer's form guidelines, "the first invalid input should be focused and scrolled into the viewport". There are two problems with the current implementation:

1. The validation message is attached to a wrapping <div> element and should instead be attached to the wrapping <fieldset> element. This is causing screen readers to skip announcing the validation message.
2. The autofocus attribute is not present on any element.

This PR fixes both issues. See this Slack discussion (internal only) for additional details.

Integration

No changes necessary in production.

Risk Assessment

• Low risk the change is small, highly observable, and easily rolled back.
• Medium risk changes that are isolated, reduced in scope or could impact few users. The change will not impact library availability.
• High risk changes are those that could impact customers and SLOs, low or no test coverage, low observability, or slow to rollback.

What approach did you choose and why?

See the linked Slack discussion above.

Accessibility

• No new axe scan violation - This change does not introduce any new axe scan violations.

This PR does not fix an axe scan violation, but it does address two accessibility audit issues, see (internal only):

1. https://github.com/github/accessibility-audits/issues/7568
2. https://github.com/github/accessibility-audits/issues/7569

Merge checklist

• Added/updated tests
• Added/updated documentation
• Added/updated previews (Lookbook)
• Tested in Chrome
• Tested in Firefox
• Tested in Safari
• Tested in Edge

[changeset-bot]

🦋 Changeset detected

Latest commit: f53fd5d

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@primer/view-components	Patch

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[acbreton]

Thanks for the help on this!