fix(search): restore full-text search for posts with description (#2557)

_includes/related-posts.html

@@ -82,7 +82,7 @@
               {% include datetime.html date=post.date lang=include.lang %}
               <h4 class="pt-0 my-2">{{ post.title }}</h4>
               <div class="text-muted">
-                <p>{% include post-description.html %}</p>
+                <p>{% include post-summary.html %}</p>
               </div>
             </div>
           </a>