Merge pull request #27592 from shuuji3/patch-7

Change the page title from "Secrets" to "Secret"

Author: k8s-ci-robot

content/ja/docs/concepts/configuration/secret.md

@@ -1,5 +1,5 @@
 ---
-title: Secrets
+title: Secret
 content_type: concept
 feature:
   title: Secretと構成管理