Using async/await in test mode without Ember.run

Question

I'm trying to use async/await functions in an Ember 2.9 project.I have this simple code :

import Route from 'ember-route';

export default Route.extend({
  async model(params) {
    const activity = await this.store.findRecord('activity', params.activity_id);

    this.set('activity', activity);

    return activity.get('courses');
  }
});

I works on dev mode but when I run a test, I have this message :

You have turned on testing mode, which disabled the run-loop's autorun. You will need to wrap any code with asynchronous side-effects in a run

I understood than I can use Ember.run but using async/await become completly useless.

Is there a solution ?

Update 1

I tried to do Ember.testing = false and it works but I'm not sure it's safe. I think I will have problems later. What you think?

Update 2

import destroyApp from '../helpers/destroy-app';
import {describe, it, beforeEach, afterEach} from 'mocha';
import {expect} from 'chai';
import startApp from '../helpers/start-app';
import {authenticateSession} from '../helpers/ember-simple-auth';
import page from 'tiny/tests/pages/courses';

describe('Acceptance: Courses', ()=> {
  let application;

  beforeEach(function () {
    $.Velocity.mock = true;
    application = startApp();
    authenticateSession(application, {data: {attributes: {fullaccess: true, 'access-token': 123}}});
  });

  afterEach(function () {
    destroyApp(application);
  });

  it('can view list of courses', function () {
    const activity = server.create('activity');

    server.create('course', {activity: activity, name: 'Test course'});
    visit('/kohorde-admin/activities/1/courses');

    andThen(()=> {
      expect(page.coursesCount()).to.eq(1);
    });
  });
});