feat(live-region-element): add tag name to HTMLElementTagNameMap

[joshblack]

Add live-region to the HTMLElementTagName map so that tools like querySelector work as-expected by giving you access to LiveRegionElement instead of a default HTMLElement

Thanks @khiga8 for pointing out that this was not working over in: #4 (review) ✨

Changelog

New

Changed

• Add live-region to HTMLElementTagName global

Removed

Testing & Reviewing

• Import the define entrypoint in a test file (or just write this in the define file itself)
• Write document.querySelector('live-region')
• Verify that the type points to LiveRegionElement | null and not HTMLElement