mp4Settings
construct an aws.sdk.kotlin.services.mediaconvert.model.Mp4Settings inside the given block
These settings relate to your MP4 output container. You can create audio only outputs with this container. For more information, see https://docs.aws.amazon.com/mediaconvert/latest/ug/supported-codecs-containers-audio-only.html#output-codecs-and-containers-supported-for-audio-only.