Cleanup property mapping types (#6388) (#6389)

* Cleanup the property mapping types
* Update target framework for JsonNetSerializer
* Rename type
* Update compiler directives
* Add equals and gethashcode to PropertyMapping
* Make PropertyMapping readonly
* Finish PropertyMapping
* Fix BOM

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

Author: github-actions[bot]

src/Elastic.Clients.Elasticsearch.JsonNetSerializer/ConnectionSettingsAwareSerializerBase.PropertyMappingProvider.cs

@@ -28,14 +28,15 @@ private static PropertyMapping FromAttributes(MemberInfo memberInfo)
 		{
 			var jsonProperty = memberInfo.GetCustomAttribute<JsonPropertyAttribute>(true);
 			var dataMemberProperty = memberInfo.GetCustomAttribute<DataMemberAttribute>(true);
-			//var propertyName = memberInfo.GetCustomAttribute<PropertyNameAttribute>(true);
-			var ignore = memberInfo.GetCustomAttribute<IgnoreAttribute>(true);
 			var jsonIgnore = memberInfo.GetCustomAttribute<JsonIgnoreAttribute>(true);
 
-			if (jsonProperty == null && ignore == null /*&& propertyName == null*/ && dataMemberProperty == null && jsonIgnore == null) return null;
+			if (jsonProperty is null && dataMemberProperty is null && jsonIgnore is null) return default;
 
 			return new PropertyMapping
-				{ Name = /*propertyName?.Name ??*/ jsonProperty?.PropertyName ?? dataMemberProperty?.Name, Ignore = ignore != null || jsonIgnore != null };
+			{
+				Name = jsonProperty?.PropertyName ?? dataMemberProperty?.Name,
+				Ignore = jsonIgnore != null
+			};
 		}
 	}
 }

src/Elastic.Clients.Elasticsearch.JsonNetSerializer/Elastic.Clients.Elasticsearch.JsonNetSerializer.csproj

@@ -10,7 +10,7 @@
   <PropertyGroup>
     <IsPackable>true</IsPackable>
     <GenerateDocumentationFile>true</GenerateDocumentationFile>
-    <TargetFrameworks>netstandard2.0;net461</TargetFrameworks>
+    <TargetFrameworks>netstandard2.0;net461;netstandard2.1;netcoreapp3.1;net5.0;net6.0</TargetFrameworks>
   </PropertyGroup>
   <ItemGroup>
     <PackageReference Include="Newtonsoft.Json" Version="12.0.1" />