fix accessibility violation by moving text to top of dialog on SelectPanel

[owenniblock]

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What are you trying to accomplish?

The accessibility violation goes away if the content is presented at the top of the container element. Maybe it's not the best design wise so suggesting we make this change for now and then see if design want us to do some work to fix this in a different way.

Screenshots

Screenshots can be found here

Integration

No

List the issues that this change affects.

Closes https://github.com/github/primer/issues/3958
Closes https://github.com/github/primer/issues/4019

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.

Just a small layout tweak.

What approach did you choose and why?

This is the simplest way to fix the accessibility violation.

Anything you want to highlight for special attention from reviewers?

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

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[changeset-bot]

🦋 Changeset detected

Latest commit: 0cab61d

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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[github-actions]

⚠️ Visual differences found

Our visual comparison tests found UI differences. Please review the differences by viewing the files changed tab to ensure that the changes were intentional.

Review visual differences

[keithamus]

This LGTM but @langermank or @lukasoppermann should also check this over.