update bilingual

lib/views/admin/markdown.html

@@ -6,7 +6,7 @@
 {% block content_head %}
 <div class="header-wrap">
   <header id="page-header">
-    <h1 class="title" id="">Markdown設定</h1>
+    <h1 class="title" id="">{{ t('Markdown settings') }}</h1>
   </header>
 </div>
 {% endblock %}