function deriveEnvVar(key, paths) {
  let configPath = paths.join('_')
  configPath = configPath ? `${configPath}_` : configPath
  return `NEW_RELIC_${configPath.toUpperCase()}${key.toUpperCase()}`
}
Creates an env var mapper from the configuration path value

@param {string} key of configuration value
@param {Array} paths list of leaf nodes leading to configuration value
@returns {string} formatted env var name