update / improve JP version

Author: tamasan238

wolfSSL/mkdocs-ja.yml

@@ -2,7 +2,7 @@ site_name: wolfSSL Manual
 site_url: https://wolfssl.com/
 docs_dir: build/html/
 site_dir: html/
-copyright: Copyright © 2023 wolfSSL Inc.
+copyright: Copyright © 2025 wolfSSL Inc.
 nav:
     - "1. 序章": index.md
     - "2. wolfSSLのビルド": chapter02.md