[#365] settlement/basic: Check amount of collected assets

Some transfers from container owners into bank account may
fail due to lack of assets, so we have to deal with remaining
amount of assets in banking account.

Signed-off-by: Alex Vanin <alexey@nspcc.ru>

pkg/innerring/processors/settlement/basic/distribute.go

@@ -1,6 +1,20 @@
 package basic
 
+import (
+	"go.uber.org/zap"
+)
+
 func (inc *IncomeSettlementContext) Distribute() {
 	inc.mu.Lock()
 	defer inc.mu.Unlock()
+
+	bankBalance, err := inc.balances.Balance(inc.bankOwner)
+	if err != nil {
+		inc.log.Error("can't fetch balance of banking account",
+			zap.String("error", err.Error()))
+
+		return
+	}
+
+	_ = bankBalance
 }