function findCGroupsV1(callback, logger = log) {
  common.readProc(CGROUPS_V1_PATH, function getCGroup(_, data) {
    if (!data) {
      logger.debug({ utilization: 'docker' }, `${CGROUPS_V1_PATH} not found, exiting parsing containerId.`)
      return callback(null)
    }

    let id = null
    parseCGroupsV1(data, 'cpu', function forEachCpuGroup(cpuGroup) {
      const match = /(?:^|[^0-9a-f])([0-9a-f]{64})(?:[^0-9a-f]|$)/.exec(cpuGroup)
      if (match) {
        id = match[1]
        return false
      }

      return true
    })

    if (id) {
      vendorInfo = { id }
      logger.debug({ utilization: 'docker' }, `Found docker id from cgroups v1: ${id}`)
      callback(null, vendorInfo)
    } else {
      logger.debug({ utilization: 'docker' }, 'No matching cpu group found.')
      callback(null, null)
    }
  })
}
Read /proc/self/cgroup and try to extract the container id from a cpu line
e.g. - `4:cpu:/docker/f37a7e4d17017e7bf774656b19ca4360c6cdc4951c86700a464101d0d9ce97ee`

@param {Function} callback function to call when done
@param {object} [logger] internal logger instance