Downgrade duplicate nonce logs to debug (filecoin-project#4933)

* add messagepool duplicate nonce print info

* update log.Info to log.debug and go fmt

* recover the grouping of imports

* update print from info to debug

* print format %w to %s

chain/messagepool/messagepool.go

@@ -240,10 +240,13 @@ func (ms *msgSet) add(m *types.SignedMessage, mp *MessagePool, strict, untrusted
 			// check if RBF passes
 			minPrice := ComputeMinRBF(exms.Message.GasPremium)
 			if types.BigCmp(m.Message.GasPremium, minPrice) >= 0 {
-				log.Infow("add with RBF", "oldpremium", exms.Message.GasPremium,
+				log.Debugw("add with RBF", "oldpremium", exms.Message.GasPremium,
 					"newpremium", m.Message.GasPremium, "addr", m.Message.From, "nonce", m.Message.Nonce)
 			} else {
-				log.Info("add with duplicate nonce")
+				log.Debugf("add with duplicate nonce. message from %s with nonce %d already in mpool,"+
+					" increase GasPremium to %s from %s to trigger replace by fee: %s",
+					m.Message.From, m.Message.Nonce, minPrice, m.Message.GasPremium,
+					ErrRBFTooLowPremium)
 				return false, xerrors.Errorf("message from %s with nonce %d already in mpool,"+
 					" increase GasPremium to %s from %s to trigger replace by fee: %w",
 					m.Message.From, m.Message.Nonce, minPrice, m.Message.GasPremium,