Prevent scrolling when activating ActionMenu form items via space

[camertron]

What are you trying to accomplish?

This PR prevents scrolling when activating a single-select ActionMenu item that submits a form. I tried pretty hard to write a test for this but the behavior does not appear in Lookbook for some reason. I verified this will fix the issue in dotcom though, and I left a number of comments.

Integration

No changes necessary in production.

List the issues that this change affects.

Fixes https://github.com/github/primer/issues/2794

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 inline comments.

Accessibility

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

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: 3b824e0

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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