i18n(ko-KR): update internationalization.mdx, api-reference.mdx, …

…`configuration-reference.mdx`, `missing-index-for-internationalization.mdx` (#7872)

* i18n(ko-KR): update `api-reference.mdx`

* i18n(ko-KR): update `i18n.mdx`

* fix: update broken link in `i18n.mdx`

* i18n(ko-KR): update `configuration-reference.mdx`

* fix: update broken links

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Co-authored-by: Yan <61414485+yanthomasdev@users.noreply.github.com>