In real applications, your `onChange` handler wont be called if the
value did not change, so the tests shouldn't either. This is another
step toward us not using Simulate at all.

When using `fireEvent.change` make sure that you're setting the value
to change to via: `{target: {value: 'the value'}}` as the second arg.

BREAKING CHANGE: If you used the old form of value changes you'll need to update your code to the new form:

Before:

```js
formField.value = newValue;
fireEvent.change(formField);
```

After:

```js
fireEvent.change(formField, {target: {value: newValue}});
```