Use correct permission names from Stoelindeling

CHANGELOG.rst

@@ -15,6 +15,7 @@ Fixed
 * Register absence form wasn't accessible without direct access to class register.
 * Printing the full group register failed when a person had no personal notes.
 * Data checks reported all Lesson Documentations as being during Holidays if there was no Holiday object.
+* Group owners couldn't create new seating plans.
 
 `2.1`_ - 2022-06-25
 -------------------

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

@@ -55,7 +55,7 @@
           <i class="material-icons left small orange-text">warning</i>
           {% trans "There is no seating plan for this lesson." %}
         </div>
-        {% has_perm "stoelindeling.add_seatingplan_rule" user first_group as can_add %}
+        {% has_perm "stoelindeling.create_seatingplan_rule" user first_group as can_add %}
         {% if can_add %}
           <div class="row margin-bottom">
             <div class="col s12">
@@ -69,7 +69,7 @@
           </div>
         {% endif %}
         {% for parent_group in first_group.parent_groups.all %}
-          {% has_perm "stoelindeling.add_seatingplan_rule" user parent_group as can_add %}
+          {% has_perm "stoelindeling.create_seatingplan_rule" user parent_group as can_add %}
           {% if can_add %}
             <div class="row">
               <div class="col s12">