message: add sinon setup to test helper
diff: @@ -4,9 +4,12 @@ import * as QUnit from 'qunit';
  import { setApplication } from '@ember/test-helpers';
  import { setup } from 'qunit-dom';
  import { start } from 'ember-qunit';
  +import setupSinon from 'ember-sinon-qunit';
  setApplication(Application.create(config.APP));
  setup(QUnit.assert);
  +setupSinon();
  +
  start();
  