Fix: Edit/deleting tasks in a challenge appears possible for people who are not admin/the creator (#11349)

* Fix: introduce new prop showOptions for task component

- Pull showOptions propr from challenge container to task itself to restrict editing for non leader of challenge users

* Fix: for group plan edit/delete tasks

website/client/components/challenges/challengeDetail.vue

@@ -57,6 +57,7 @@
         :type="column",
         :key="column",
         :taskListOverride='tasksByType[column]',
+        :showOptions="showOptions",
         @editTask="editTask",
         @taskDestroyed="taskDestroyed",
         v-if='tasksByType[column].length > 0')
@@ -251,6 +252,9 @@ export default {
     canJoin () {
       return !this.isMember;
     },
+    showOptions () {
+      return this.isLeader;
+    },
   },
   mounted () {
     if (!this.searchId) this.searchId = this.challengeId;