"""\nabc\n""" and """abc""" are not distinguishable from the ast

Both of then look exactly the same. I would expect \n to be part of the value.

```js
"""abc"""
type T {
  a: Int
}

"""
abc
"""
type T {
  a: Int
}

```

```js
{ kind: 'StringValue',
  value: 'abc',
  block: true,
  loc: { start: 0, end: 9 } }
{ kind: 'StringValue',
  value: 'abc',
  block: true,
  loc: { start: 31, end: 42 } }
```