Merge branch 'boards-assignee-title-fix' into 'master'

Fix broken assigee title component prop

See merge request gitlab-org/gitlab!47397

app/assets/javascripts/sidebar/components/assignees/assignee_title.vue

@@ -29,7 +29,8 @@ export default {
     },
     changing: {
       type: Boolean,
-      required: true,
+      required: false,
+      default: false,
     },
   },
   computed: {