Pass lambda environment variables as part of the function field

[betabandido]

At this moment Terraform does not allow nested maps or lists with more than 2 levels of depth. Because of that, environment variables in the lambda module cannot be defined within the functions field. If that limitation gets solved, change the lambda module so that it supports the following syntax:

  functions = {
    LambdaTestHello = {
      handler = "package.say_hello"
    }
    LambdaTestPrintVars = {
      handler = "package.print_vars"
      variables = {
        foo = "FOO"
        bar = "BAR"
      }
    }
  }