AWS LAMBDA で AWS_ACCESS_KEY_ID の環境変数を使うとエラーになる

AWS LAMBDA で AWS_ACCESS_KEY_ID の環境変数を使うとエラーになる:

こちらのエラーがでて、時間無駄にしてしまったのでメモ

An error occurred: ScreenshotLambdaFunction - Lambda was unable to configure your environment variables because the environment variables you have provided contains reserved keys that are currently not supported for modification. Reserved keys used in this request:AWS_ACCESS_KEY_ID, AWS_SECRET_ACCESS_KEY (Service: AWSLambdaInternal; Status Code: 400; Error Code: InvalidParameterValueException; Request ID: XXXX). 

こちら README.md にも書いてありましたね。

Credentials

We recommend using a tool like AWS Vault to manage your AWS credentials.

You must configure your AWS credentials either by defining AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY environmental variables, or using an AWS profile. You can read more about this on the Serverless Credentials Guide.

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