Move warning in absence creation dialog to top

aleksis/apps/alsijil/frontend/components/coursebook/absences/AbsenceCreationSummary.vue

 <template>
   <div>
+    <message-box dense type="warning" class="mt-5">
+      {{ $t("alsijil.coursebook.absences.warning") }}
+    </message-box>
     <!-- MAYBE introduce a minimal variant of CRUDIterator -->
     <!--       with most features disabled for this list usecase -->
     <c-r-u-d-iterator
@@ -64,9 +67,6 @@
         </v-expansion-panels>
       </template>
     </c-r-u-d-iterator>
-    <message-box dense type="warning" class="mt-5">
-      {{ $t("alsijil.coursebook.absences.warning") }}
-    </message-box>
   </div>
 </template>