Error: Query root type must be provided

I seem to be getting this error:

https://github.com/prismagraphql/graphql-import/issues/73

I'm running 0.0.10, with a schema generated by `graphql-cli` from a gatsby project:

```graphql
# source: http://0.0.0.0:8000/___graphql
# timestamp: Sat Jul 28 2018 17:46:31 GMT+0000 (Greenwich Mean Time)

schema {
query: RootQueryType
}

"""
A date string, such as 2007-12-03, compliant with the ISO 8601 standard for
representation of dates and times using the Gregorian calendar.
"""
scalar Date

# ...
```

Here's the full error:
```
(node:15016) UnhandledPromiseRejectionWarning: Unhandled promise rejection (rejection id: 1): Error: Query root type must be provided.
(node:15016) DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.
```
No stack trace, unfortunately.