Changed function syntax to be same as events.vue

vue-theme/src/components/sidebars/exhibitions.vue

@@ -34,7 +34,9 @@ export default {
         async getPosts() {
             const upcoming = this.$store.dispatch(
                 `getAllExhibitions`,
-                sortTypes.currentAndUpcoming,
+                {
+                    sortType: sortTypes.currentAndUpcoming
+                }
             )
             if (upcoming.length < 1) {
                 // this.listType = 'past'