Add missing babel helper

This is needed due to https://github.com/glimmerjs/glimmer-vm/blob/e672233ea70ab2614648bb194efc107f3698baad/packages/%40glimmer/runtime/lib/compiled/opcodes/component.ts

This is probably unintended and a waste of bytes. We should fix it
upstream and remove this helper.

(cherry picked from commit fd360ca)

packages/external-helpers/lib/external-helpers.js

@@ -85,3 +85,9 @@ export function possibleConstructorReturn(self, call) {
   }
   return assertThisInitialized(self);
 }
+
+export function objectDestructuringEmpty(obj) {
+  if (DEBUG && (obj === null || obj === undefined)) {
+    throw new TypeError('Cannot destructure undefined');
+  }
+}