public Builder credentials(String credentials) {
            this.credentials = credentials;
            return this;
        }
Sets the Credentials required for invoking the authorizer, if any, in
the form of an ARN of an IAM execution role.

<p>For example, "arn:aws:iam::account-id:IAM_role".

@param credentials Credentials ARN to set.
@return Returns the builder.
smithy-aws-apigateway-traits/src/main/java/software/amazon/smithy/aws/apigateway/traits/AuthorizerDefinition.java