Navigation keys should work in Suggested Actions under IE Mode

[compulim]

Fixes #4319.

Changelog Entry

Fixed

• Fixes #4319. Fixed navigation keys not working in suggested actions under IE Mode, by @compulim, in PR #4320

Description

Under IE Mode, the keydown event will express LEFT arrow key as Left, instead of ArrowLeft. Same for other navigation keys.

Design

Specific Changes

• Updated the handleKeyDown for <RovingTabIndex> to handle both ArrowLeft and Left equally, also for other navigation keys

• I have added tests and executed them locally
• I have updated CHANGELOG.md
• I have updated documentation

Review Checklist

This section is for contributors to review your work.

• Accessibility reviewed (tab order, content readability, alt text, color contrast)
• Browser and platform compatibilities reviewed
• CSS styles reviewed (minimal rules, no z-index)
• Documents reviewed (docs, samples, live demo)
• Internationalization reviewed (strings, unit formatting)
• package.json and package-lock.json reviewed
• Security reviewed (no data URIs, check for nonce leak)
• Tests reviewed (coverage, legitimacy)