Allow general language codes in the Metadata API (#52920)
Closes #52898
LangCode Missing zh-Hans and zh-Hant
| 'yo-NG'
| 'zh-CN'
| 'zh-Hans' //added
| 'zh-Hant' //added
| 'zh-HK'
| 'zh-MO'
| 'zh-SG'
| 'zh-TW'
| 'zu-ZA'
https://github.com/vercel/next.js/blob/f5272acbe5628164257ef8e584c8a469a4af5cb8/packages/next/src/lib/metadata/types/alternative-urls-types.ts#L419
Co-authored-by: Shu Ding <3676859+shuding@users.noreply.github.com>
