terraform resource aws_lambda_function generated incorrect output

[rorourke-iot]

The resource aws_lambda_function was generated as

resource "aws_lambda_function" "<terraform id>" {
    .
    .
    .
    environment {
        variables {
            .
            .
            .
        }
    }
    .
    .
    .
}

According to the docs, variables { should be variables = {.