#1 Pointless reassignement of lastMinerRecord

https://gogs.veloe.link/Veloe/EthemineTelegramBotCore/src/master/EthermineBotTelegramCore/UpdateData.cs#L88-L90 lastMinerRecord already assigned at line 42. Assignment here assigns the same value as was before. Otherwise if emit `Botdb.SaveChangesAsync()` after `Botdb.miners.Add(newMinerRecord)` (line 46) this assignment would always lead to equality with newMinerRecord.