Update for 8.5 spec, add FieldValue and various fixes (#6732) (#6734)

* Generate on 8.5 spec which includes spec fixes

* Update for 8.5 spec, add FieldValue and various fixes

Co-authored-by: Steve Gordon <sgordon@hotmail.co.uk>

Author: github-actions[bot]

src/Elastic.Clients.Elasticsearch.JsonNetSerializer/Converters/HandleNestTypesOnSourceJsonConverter.cs

@@ -21,7 +21,7 @@ public class HandleNestTypesOnSourceJsonConverter : JsonConverter
 			typeof(QueryContainer),
 			//typeof(CompletionField),
 			//typeof(Attachment),
-			typeof(LazyDocument),
+			typeof(LazyJson),
 			//typeof(GeoCoordinate),
 			typeof(GeoLocation),
 			//typeof(CartesianPoint),