diffApply array bug

There is a bug in diffApply function from just-diff-apply package

```js
import { diff } from 'just-diff'
import { diffApply } from 'just-diff-apply'

const source = { a: [ 1, 2, 3, 4, 5 ] }

const newSource = { a: [ 1, 2, 5 ] }

const changes = diff(source, newSource) // [{ op: 'remove', path: ['a', 4] }, { op: 'remove', path: ['a', 3] }, { op: 'replace', path: ['a', 2], value: 5 }]

console.log(changes)

// Expected value is newSource, but got only the array [1, 2, 5]
const appliedChanges = diffApply(source, changes) // [1, 2, 5]

console.log(appliedChanges)
```

If I replace ```return subObject``` in diffApply function with ```return obj``` I will get correct result