Add DateTimeOffset to the known types for ObjectToInferredTypesConverter (#8380)

Author: flobernd

Diff for: src/Elastic.Clients.Elasticsearch/_Shared/Serialization/ObjectToInferredTypesConverter.cs

@@ -21,10 +21,11 @@ public override object Read(
 		{
 			JsonTokenType.True => true,
 			JsonTokenType.False => false,
-			JsonTokenType.Number when reader.TryGetInt64(out var l) => l,
+			JsonTokenType.Number when reader.TryGetInt64(out var value) => value,
 			JsonTokenType.Number => reader.GetDouble(),
-			JsonTokenType.String when reader.TryGetDateTime(out var datetime) => datetime,
-			JsonTokenType.String => reader.GetString(),
+			JsonTokenType.String when reader.TryGetDateTime(out var value) => value,
+			JsonTokenType.String when reader.TryGetDateTimeOffset(out var value) => value,
+			JsonTokenType.String => reader.GetString()!,
 			_ => JsonDocument.ParseValue(ref reader).RootElement.Clone()
 		};