imports with `as` get corrupted

Turns

```js
import {
  setupTest as _setupTest,
  setupRenderingTest as _setupRenderingTest
} from 'ember-qunit';
```

into

```js
import {
  setupTest,
  setupRenderingTest
} from 'ember-qunit';
```

That's the only change in the file, the corresponding uses were not touched.