Fix grain price fetcher

src/Managing.Application.Abstractions/Repositories/ICandleRepository.cs

@@ -25,4 +25,5 @@ public interface ICandleRepository
         Enums.Timeframe timeframe,
         DateTime start);
     Task InsertCandle(Candle candle);
+    Task InsertCandles(IEnumerable<Candle> candles);
 }