fix: Fix a missing comma

Fixed the missing comma after the Ukrainian translation in the book translations section of the website sidebar, aligning it with the formatting used in other language sections.

Author: E-namel

layouts/partials/translations.html

@@ -17,7 +17,7 @@
     <tr><td><a href="{{ partial "translated-chapter.html" (dict "ctx" . "lang" "ru") }}">Русский</a>,</td></tr>
     <tr><td><a href="{{ partial "translated-chapter.html" (dict "ctx" . "lang" "sl") }}">Slovenščina</a>,</td></tr>
     <tr><td><a href="{{ partial "translated-chapter.html" (dict "ctx" . "lang" "tl") }}">Tagalog</a>,</td></tr>
-    <tr><td><a href="{{ partial "translated-chapter.html" (dict "ctx" . "lang" "uk") }}">Українська</a></td></tr>
+    <tr><td><a href="{{ partial "translated-chapter.html" (dict "ctx" . "lang" "uk") }}">Українська</a>,</td></tr>
     <tr><td><a href="{{ partial "translated-chapter.html" (dict "ctx" . "lang" "zh") }}">简体中文</a>,</td></tr>
   </table>
 </p>