Shorten long author names in guide listing to make room for heart count

- This was leading to overlap of long names and the heart count on the
  production site.

pskb_website/templates/article_list.html

@@ -78,7 +78,7 @@
 
                                                     <span class="name">{{article|author_name|truncate(18, True)}}</span>
                                                     {% if article.author_name != article.author_real_name %}
-                                                    <span class="gh-name">@{{article.author_name|truncate(23)}}</span>
+                                                    <span class="gh-name">@{{article.author_name|truncate(18)}}</span>
                                                     {% endif %}
                                                 </p>