Replace the setup-qunit rejects implementation Ember.onerror -> windo…

…w.onerror

packages/internal-test-helpers/lib/ember-dev/setup-qunit.ts

@@ -1,5 +1,3 @@
-import Ember from 'ember';
-
 import { getDebugFunction, setDebugFunction } from '@ember/debug';
 import { DEBUG } from '@glimmer/env';
 
@@ -13,8 +11,6 @@ import type { DebugEnv } from './utils';
 import { setupWarningHelpers } from './warning';
 
 declare global {
-  let Ember: any;
-
   interface Assert {
     rejects(promise: Promise<any>, expected?: string | RegExp, message?: string): Promise<any>;
 
@@ -55,9 +51,9 @@ export default function setupQUnit() {
     message?: string
   ) {
     let error: unknown;
-    let prevOnError = Ember.onerror;
+    let prevOnError = window.onerror;
 
-    Ember.onerror = (e: Error) => {
+    window.onerror = (e: string | Event) => {
       error = e;
     };
 
@@ -77,7 +73,7 @@ export default function setupQUnit() {
       message
     );
 
-    Ember.onerror = prevOnError;
+    window.onerror = prevOnError;
   };
 
   QUnit.assert.throwsAssertion = function (