Fix grain price fetcher

src/Managing.Infrastructure.Database/InfluxDb/CandleRepository.cs

@@ -111,9 +111,9 @@ public class CandleRepository : ICandleRepository
         return results;
     }
 
-    public async Task InsertCandle(Candle candle)
+    public Task InsertCandle(Candle candle)
     {
-        await _influxDbRepository.WriteAsync(write =>
+        _influxDbRepository.Write(write =>
         {
             PriceDto price = PriceHelpers.Map(candle);
             write.WriteMeasurement(
@@ -121,8 +121,25 @@ public class CandleRepository : ICandleRepository
                 WritePrecision.Ns,
                 _priceBucket,
                 _influxDbRepository.Organization);
-            return Task.CompletedTask;
         });
+        return Task.CompletedTask;
+    }
+
+    public Task InsertCandles(IEnumerable<Candle> candles)
+    {
+        _influxDbRepository.Write(write =>
+        {
+            foreach (var candle in candles)
+            {
+                PriceDto price = PriceHelpers.Map(candle);
+                write.WriteMeasurement(
+                    price,
+                    WritePrecision.Ns,
+                    _priceBucket,
+                    _influxDbRepository.Organization);
+            }
+        });
+        return Task.CompletedTask;
     }
 
     public void Test(Candle candle)