message: reduce the penalty for disjointed PoS header chain, because a single peer can send us a single header when chain updates to new tip
diff: @@ -3223,7 +3223,7 @@ bool ProcessNewBlockHeaders(uint32_t& nPoSTemperature, const uint256& lastAccept
  int nCooling = POW_HEADER_COOLING;
  if (headers[0].hashPrevBlock != lastAcceptedHeader && !lastAcceptedHeader.IsNull()) {
  - nPoSTemperature += nCooling;
  + nPoSTemperature += (18 + headers.size()) / 10;
  nCooling = 0;
  }
  