fix: Fix storybook (no-changelog) (#4624)

since we migrated to vite, storybook/webpack aren't doing all the babel transforms. that's we we need to revert all optional-chaining and nullish-coalescing in design-system.

Hopefully this will be remedied after we move to vite for storybook.

packages/design-system/src/components/N8nMenuItem/MenuItem.vue

@@ -134,7 +134,7 @@ export default Vue.extend({
 				} else if (item.activateOnRouteNames) {
 					return (
 						Array.isArray(item.activateOnRouteNames) &&
-						item.activateOnRouteNames.includes(this.$route.name ?? '')
+						item.activateOnRouteNames.includes(this.$route.name || '')
 					);
 				}
 				return false;