Refactor abstract classes handling for scripting types creation (eg. Script or GPUResource) under dotnet7

Source/Tools/Flax.Build/Bindings/BindingsGenerator.CSharp.cs

@@ -1227,6 +1227,10 @@ namespace Flax.Build.Bindings
 
             GenerateCSharpManagedTypeInternals(buildData, classInfo, contents, indent);
 
+            // Abstract wrapper (to ensure C# class can be created for Visual Scripts, see NativeInterop.NewObject)
+            if (classInfo.IsAbstract)
+                contents.AppendLine().Append(indent).Append("[Unmanaged] private sealed class AbstractWrapper : ").Append(classInfo.Name).AppendLine(" { }");
+
             // Nested types
             foreach (var apiTypeInfo in classInfo.Children)
             {