Don't transfer zero FIL during rebalancing fork

chain/stmgr/forks.go

@@ -312,12 +312,14 @@ func UpgradeFaucetBurnRecovery(ctx context.Context, sm *StateManager, cb ExecCal
 				available = st.GetAvailableBalance(act.Balance)
 			}
 
+			if !available.IsZero() {
 				transfers = append(transfers, transfer{
 					From: addr,
 					To:   builtin.ReserveAddress,
 					Amt:  available,
 				})
 			}
+		}
 		return nil
 	})
 	if err != nil {