Ko: 1st Korean l10n work for release-1.20

- Translate reference/glossary/persistent-volume.md in Korean (#25474)
- Update outdated files in the dev-1.20-ko.1 branch (1) (#25576)
- Translate blog/dont-panic-kubernetes-and-docker into Korean (#25596)
- Update outdated files in the dev-1.20-ko.1 branch(3) (#25728)
- Ko: enhance tutorials//cluster-intro translation (#25754)
- Fix Outdated files in the dev-1.20-ko.1 branch (2) (#25765)

Co-authored-by: seokho-son <shsongist@gmail.com>
Co-authored-by: jmyung <jesang.myung@gmail.com>
Co-authored-by: Jerry Park <jaehwa@gmail.com>
Co-authored-by: santachopa <santachopa@naver.com>
Co-authored-by: SEUNGHYUN KO <kosehy@gmail.com>
Co-authored-by: June Yi <gochist@gmail.com>

content/ko/blog/_index.md

@@ -0,0 +1,16 @@
+---
+title: 쿠버네티스 블로그
+linkTitle: 블로그
+menu:
+  main:
+    title: "블로그"
+    weight: 40
+    post: >
+       <p>쿠버네티스와 컨테이너 전반적 영역에 대한 최신 뉴스도 읽고, 방금 나온 따끈따끈한 기술적 노하우도 알아보세요.</p>
+---
+{{< comment >}}
+
+블로그에 기여하는 방법에 대한 자세한 내용은
+https://kubernetes.io/docs/contribute/new-content/blogs-case-studies/#write-a-blog-post 를 참고하세요.
+
+{{< /comment >}}