Mark api.HTMLAllCollection as deprecated

[AzazelSensei]

Summary

Mark api.HTMLAllCollection (and item / length / namedItem) as deprecated so it matches Document.all and the MDN page.

Test results and supporting details

• api.Document.all is already deprecated: true (spec: https://html.spec.whatwg.org/multipage/obsolete.html#dom-document-all)
• MDN already treats the interface as deprecated: https://developer.mozilla.org/en-US/docs/Web/API/HTMLAllCollection
• annevk on Fix document.all whatwg/html#9298 (comment): the API is deprecated, just can't be removed
• Same status pattern as HTMLMarqueeElement

Related issues

Fixes #30340

[github-actions]

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[Elchi3]

Thank you! 👍