function _hasAwsContainerApi() {
  if (process.env.ECS_CONTAINER_METADATA_URI_V4 != null) {
    return true
  }
  return process.env.ECS_CONTAINER_METADATA_URI != null
}
Inspects the running environment to determine if the AWS ECS metadata API
is available.

@see https://docs.aws.amazon.com/AmazonECS/latest/developerguide/ec2-metadata.html

@returns {boolean}