Seventh Korean l10n work for release-1.13 (#12981)

* ko-trans: Update outdated contents in ko7 branch (#12762)

* ko: Update outdated files in dev-1.13-ko.7 (#12805)

* ko: Translate docs/home/_index.md in Korean (#12829)

* Translate scheduler-perf-tuning.md in Korean (#12782)

* Translate concepts/overview/object-management-kubectl/overview in Korean (#12834)

* Fix new line in Korean translation scheduler-perf-tuning.md (#12835)

* ko: Translate tutorials/online-training/overview.md in Korean (#12854)

* ko: Translate contribute/_index.md in Korean (#12850)

* ko: Update localization guide about instruction-type content (#12877)

Co-authored-by:    June Yi <june.yi@samsung.com>
Co-authored-by:    Claudia J.Kang <claudiajkang@gmail.com>
Co-authored-by:    Seokho <shsongist@gmail.com>
Co-authored-by:    Kim Young Dae <38598117+zer0big@users.noreply.github.com>

content/ko/docs/home/_index.md

@@ -12,5 +12,5 @@ menu:
     title: "문서"
     weight: 20
     post: >
-      <p>Learn how to use Kubernetes with conceptual, tutorial, and reference documentation. You can even <a href="/editdocs/" data-auto-burger-exclude>help contribute to the docs</a>!</p>
+      <p>개념, 튜토리얼 및 참조 문서와 함께 쿠버네티스 사용하는 방법을 익힐 수 있다. 또한, <a href="/editdocs/" data-auto-burger-exclude>문서에 기여하는 것도 도움을 줄 수 있다</a>!</p>
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