`change` is missing in props.fields

### Are you submitting a **bug report** or a **feature request**?

bug report

### What is the current behavior?

After update to v3 function `change` is missing in props.fields

v3.1.0 https://codesandbox.io/s/react-final-form-field-arrays-qeeu5

### What is the expected behavior?

`props.fields.change` is not undefined

v1.0.4 https://codesandbox.io/s/react-final-form-field-arrays-02s9n

### What's your environment?
```
"final-form": "4.8.2",
"final-form-arrays": "3.0.1",
"react": "16.8.6",
"react-dom": "16.8.6",
"react-final-form": "6.3.0",
"react-final-form-arrays": "3.1.0",
```
windows 10, chrome 75

### Other information

Maybe it's bug in `useField` from `react-final-form`.
Cuz if I call `useForm().getFieldState(name)` instead `useField(name)` I see missing fieldState props

https://github.com/final-form/react-final-form-arrays/blob/master/src/useFieldArray.js#L59