Hide period field for break slots

aleksis/apps/lesrooster/frontend/components/lesson_raster/SlotCreator.vue

@@ -126,7 +126,7 @@ export default defineComponent({
     </template>
 
     <template #content>
-      <div aria-required="true">
+      <div v-if="!breaks" aria-required="true">
         <positive-small-integer-field
           v-model="slots.period"
           :label="$t('lesrooster.slot.period')"