Fix number of blog posts on front page

templates/frontpage/blog.html

@@ -3,7 +3,7 @@
   <div class="container">
     <h2 class="title is-2">{{ title | default(value="Aus dem Teckids-Blog") }}</h2>
     <div class="columns is-multiline is-same-height mt-4">
-      {% for post in blog_section.pages | slice(end=4) %}
+      {% for post in blog_section.pages | slice(end=6) %}
         <div class="column is-one-third">
           {% include "blog/card.html" %}
         </div>