Inconsistent response between required and optional fields
### Issue Description

Querying fields that is required / not required provides inconsistent responses.

Consider the repro - there are 2 fields that can be queried ```willFailFieldIsRequired``` and ```willFailFieldIsNotRequired``` both return a string and the only difference is that one field is required and the other is not. the resolvers for both fields throws an error meaning that both will fail. However the shape of the response differs.

```willFailFieldIsRequired``` returns the expected errors array with the data property as null

```
  errors: [
    {
      message: 'something went wrong',
      locations: [Array],
      path: [Array],
      extensions: [Object]
    }
  ],
  data: null
}
```

```willFailFieldIsNotRequired ``` returns the expected errors array, but the data property is an object with the key ```willFailFieldIsNotRequired``` as null.
```
{
  errors: [
    {
      message: 'something went wrong',
      locations: [Array],
      path: [Array],
      extensions: [Object]
    }
  ],
  data: { willFailFieldIsNotRequired: null }
}
```


Other than the fact that this is inconsistent it causes issues with apollo client, because querying a field that is required if the resolver throws an error the Apollo client fails with ```null is not an object (evaluating 'rootValue[aliasedFieldName]')``` because the clients expects the aliasedFieldName to be present within data. And it only is if the field is optional.

This essentially means it is impossible to have any required field be able to throw an error.

### Link to Reproduction

https://stackblitz.com/edit/node-datsna?file=index.mjs

### Reproduction Steps

- Open link
- npm start
- check logs