Fix HTML bug. Commit ready for merge.

 - Legacy-Id: 9967

Author: larseggert

ietf/templates/meeting/group_materials.html

@@ -8,7 +8,7 @@
     <a name="session.group-{{ session.group.acronym }}"></a>
     {% endcomment %}
     {% if session.name %}
-      <div class="anchor-target" id="{{ session.name }}">{{ session.name }}</div>
+      <div class="anchor-target" id="{{ session.name|slugify }}">{{ session.name }}</div>
     {% else %}
       <div class="anchor-target" id="{{session.group.acronym}}">{{session.group.acronym}}</div>
       {% if session.group.state.slug == "bof" %}