Add classes for custom spans implementation

Author: sjuarezgx

dotnet/src/dotnetcore/GxClasses/GxClasses.csproj

@@ -120,7 +120,6 @@
   </ItemGroup>
 
   <ItemGroup>
-    <Folder Include="Diagnostics\" />
     <Folder Include="Helpers\Cryptography\Hashing\" />
     <Folder Include="Domain\SD\" />
     <Folder Include="Attributes\" />