message: [refactor] Use uint64_t and std namespace in PoissonNextSend
diff: @@ -718,6 +718,6 @@ void RandomInit()
  std::chrono::microseconds PoissonNextSend(std::chrono::microseconds now, std::chrono::seconds average_interval)
  {
  - double unscaled = -log1p(GetRand(1ULL << 48) * -0.0000000000000035527136788 /* -1/2^48 */);
  + double unscaled = -std::log1p(GetRand(uint64_t{1} << 48) * -0.0000000000000035527136788 /* -1/2^48 */);
  return now + std::chrono::duration_cast<std::chrono::microseconds>(unscaled * average_interval + 0.5us);
  }
  