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- Update outdated files in the dev-1.20-ko.1 branch (1) (#25576)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- Update outdated files in the dev-1.20-ko.1 branch(3) (#25728)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- Fix Outdated files in the dev-1.20-ko.1 branch (2) (#25765)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/examples/application/mysql/mysql-configmap.yaml

@@ -5,12 +5,12 @@ metadata:
   labels:
     app: mysql
 data:
-  master.cnf: |
-    # Apply this config only on the master.
+  primary.cnf: |
+    # Primary에만 이 구성을 적용한다.
     [mysqld]
     log-bin
-  slave.cnf: |
-    # Apply this config only on slaves.
+  replica.cnf: |
+    # 레플리카에만 이 구성을 적용한다.
     [mysqld]
     super-read-only