Correctly display excuse_types and extra_marks

aleksis/apps/alsijil/templates/alsijil/partials/lesson/tabs/notes.html

@@ -113,9 +113,9 @@
               </span>
             </td>
             <td><i class="material-icons center">{{ form.excused.value|yesno:"check,clear" }}</i></td>
-            <td>{% firstof form.excuse_type.value "–" %}</td>
+            <td>{% firstof form.instance.excuse_type "–" %}</td>
             <td>
-              {% for extra_mark in form.extra_marks.value %}
+              {% for extra_mark in form.instance.extra_marks.all %}
                 {{ extra_mark }}{% if not forloop.last %},{% endif %}
               {% empty %}
                 –