Node 10 (using esm) error
## index.js
```js
import { GraphQLNonNull, GraphQLList, GraphQLBoolean } from 'graphql'
import { GraphQLUpload } from 'apollo-upload-server'
import resolve from './resolver'

export default {
  type: GraphQLBoolean,
  args: {
    files: {
      type: new GraphQLList(new GraphQLNonNull(GraphQLUpload))
    }
  },
  resolve
}
```
## result
> 
```
(node:20404) UnhandledPromiseRejectionWarning: file:///Users/macbook/WebstormProjects/project/node_modules/apollo-upload-server/lib/types.mjs:1
import { GraphQLScalarType } from 'graphql'

SyntaxError: Missing export name 'GraphQLScalarType' in ES module: file:///Users/macbook/WebstormProjects/project/node_modules/graphql/index.js
    at file:///Users/macbook/WebstormProjects/project/node_modules/apollo-upload-server/lib/types.mjs:1
(node:20404) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1)
```