Enum types documentation fix
Enum types documentation fix

LanguageType is not mentioned should be LanguageEnum
rmosolgo/graphql-ruby,rmosolgo/graphql-ruby,xuorig/graphql-ruby,rmosolgo/graphql-ruby,rmosolgo/graphql-ruby,xuorig/graphql-ruby,xuorig/graphql-ruby,nevesenin/graphql-ruby,nevesenin/graphql-ruby,nevesenin/graphql-ruby,nevesenin/graphql-ruby