fix #3585 VoidResponse should not be shared #3588

Author: russcam

src/Elasticsearch.Net/Transport/Pipeline/ResponseBuilder.cs

@@ -13,7 +13,6 @@ public class ResponseBuilder<TReturn>
 	{
 		private const int BufferSize = 81920;
 		private static readonly IDisposable EmptyDisposable = new MemoryStream();
-		private static readonly VoidResponse Void = new VoidResponse();
 		private readonly CancellationToken _cancellationToken;
 		private readonly bool _disableDirectStreaming;
 
@@ -187,7 +186,7 @@ private bool SetSpecialTypes(Stream responseStream, ElasticsearchResponse<TRetur
 		private void SetVoidResult(ElasticsearchResponse<VoidResponse> result, Stream response)
 		{
 			response.Dispose();
-			result.Body = Void;
+			result.Body = new VoidResponse();
 		}
 	}
 }

src/Nest/Aggregations/Pipeline/MovingAverage/MovingAverageAggregationJsonConverter.cs

@@ -84,7 +84,7 @@ public override void WriteJson(JsonWriter writer, object value, JsonSerializer s
 		private T GetOrDefault<T>(string key, Dictionary<string, JToken> properties)
 		{
 			if (!properties.TryGetValue(key, out JToken value)) return default(T);
-#if DOTNETCORE
+#if DOTNETCORER
 			return value.ToObject<T>();
 #else
 			return (T)Convert.ChangeType(value, typeof(T));