Tenth Korean l10n work for release 1.18

- Translate concepts/extend-kubenetes/service-catalog.md in Korean (#23233)
- Translate concepts/configuration/secret.md into Korean (#23110)
- Translate tasks/extend-kubernetes/setup-extension-api-server.md into … (#22574)
- Update outdated files in dev-1.18-ko.10 branch (#23013)

Co-authored-by: Seokho Son <shsongist@gmail.com>
Co-authored-by: Jerry Park <jaehwa@gmail.com>
Co-authored-by: santachopa <santachopa@naver.com>

content/ko/docs/setup/best-practices/multiple-zones.md

@@ -74,7 +74,7 @@ federation support).
 a single master node by default.  While services are highly
 available and can tolerate the loss of a zone, the control plane is
 located in a single zone.  Users that want a highly available control
-plane should follow the [high availability](/docs/admin/high-availability) instructions.
+plane should follow the [high availability](/docs/setup/production-environment/tools/kubeadm/high-availability/) instructions.
 
 ### Volume limitations
 The following limitations are addressed with [topology-aware volume binding](/ko/docs/concepts/storage/storage-classes/#볼륨-바인딩-모드).