refactor: improve typing in tests

tests/unit/initializers/embedded-test.ts

@@ -5,9 +5,7 @@ import { module, test } from 'qunit'
 import Resolver from 'ember-resolver'
 import { run } from '@ember/runloop'
 
-import type { TestContext } from '@ember/test-helpers'
-
-type TestApplication = TestContext['owner'] & {
+type TestApplication = Application & {
   // Public types are currently incomplete, these 2 properties exist:
   // https://github.com/emberjs/ember.js/blob/v3.26.1/packages/@ember/application/lib/application.js#L376-L377
   _booted: boolean

tests/unit/services/embedded-test.ts

@@ -1,24 +1,24 @@
 import { module, test } from 'qunit'
 import { setupTest } from 'ember-qunit'
-
 import type EmbeddedService from 'ember-cli-embedded/services/embedded'
 
 module('Unit | Service | embedded', function (hooks) {
   setupTest(hooks)
 
   test('it fetches data from the config as a proxy', function (assert) {
-    this.owner.register('config:embedded', {
-      myKey: 'myValue',
-    })
+    const options = { myKey: 'myValue' };
+
+    this.owner.register('config:embedded', options)
 
-    const service = this.owner.lookup('service:embedded') as EmbeddedService
+    const service = this.owner.lookup('service:embedded') as EmbeddedService<typeof options>
 
     assert.strictEqual(
       service.get('myKey'),
       'myValue'
     )
 
     assert.strictEqual(
+      // @ts-expect-error We try to access a property which don't exist
       service.get('doesNotExist'),
       undefined
     )