error : not able to download schema having union type

[WISKesarkar]

While working on POC for GQL federation to support multiple gql apis under one service.
I found out nautius/gateway library fails to download schema with union types in it.

for testing Please refer this POC-example

Issue :

• serviceB gql schema has union named UnionTypeTest, service schema is downloaded using get-graphql-schema cli (schema is available in serviceB package and has union field with correct member types)
• When gatwayTest.go tries to fetch the schema from nautilus/gatway it fails to grab schema for union members and GQL Playground throws attached error.