message: replace more folly::Optional::reset by clear inside template
diff: @@ -193,7 +193,7 @@ folly::Optional<CongestionController::LossEvent> detectLossPackets(
  const LossVisitor& lossVisitor,
  TimePoint lossTime,
  PacketNumberSpace pnSpace) {
  - getLossTime(conn, pnSpace).clear();
  + getLossTime(conn, pnSpace).reset();
  std::chrono::microseconds delayUntilLost =
  std::max(conn.lossState.srtt, conn.lossState.lrtt) *
  conn.transportSettings.timeReorderingThreshDividend /
  