Cannot use unicode emojies

Hei, unicode emojies in a GraphQL schema such as 🦄 makes the following error :

GraphQLError: Syntax Error: Cannot parse the unexpected character <EOF>.

# Sample schema 🦄
type Query {
  user(id: Int!): User!
}

type User {
  id: Int!
  username: String!
  email: String!
  createdAt: String!
}

Perhaps updating the graphql dependency to its latest version could fix the issue.