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Only API_KEY, OPENID_CONNECT and AMAZON_COGNITO_USER_POOLS is supported
https://altairgraphql.dev/docs/features/graphql-subscriptions#aws-appsync

AWS_LAMBDA was added in 2021.
https://aws.amazon.com/cn/blogs/mobile/appsync-lambda-auth/

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Support AWS_LAMBDA in aws_appsync_authenticationType.
It uses jwt so it should be similar to OPENID_CONNECT and AMAZON_COGNITO_USER_POOLS

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