### Godot version

4.1.3

### System information

Linux

### Issue description

I'm trying to make an editor plugin on Rust:

```rust
#[derive(GodotClass)]
#[class(tool, editor_plugin, init, base=EditorPlugin)]
pub struct MyEditorPluginBase {}
```

But due to some limitations, I still have to use GDScript for some specific things.

So I tried to make a subclass of this Rust class:

```gdscript
@tool
class_name MyEditorPlugin
extends MyEditorPluginBase
```

This would work if `MyEditorPluginBase` was a GDScript class, but since it's a GDExtension class in my case, it doesn't work:

> Unable to load addon script from path: 'res://addons/my_addon/my_editor_plugin.gd' Base type is not EditorPlugin.

But it obviously **IS** EditorPlugin!

![godot-editorplugin-docs](https://github.com/godotengine/godot/assets/3236464/4665deeb-30f0-45cd-bfff-56101b9d4875)

![godot-editorplugin](https://github.com/godotengine/godot/assets/3236464/b1b6ecb4-de22-4abd-91a3-e180691f67ee)

If I understand correctly, this behavior is caused by this function, which checks some mysterious "instance base type" instead of real inheritance:

https://github.com/godotengine/godot/blob/fa4a65387ea41506ecc519fc61a06da110dce51c/editor/editor_node.cpp#L3456-L3458

https://github.com/godotengine/godot/blob/fa4a65387ea41506ecc519fc61a06da110dce51c/modules/gdscript/gdscript.cpp#L260-L263

Since the [documentation](https://docs.godotengine.org/en/stable/tutorials/plugins/editor/making_plugins.html#the-script-file) doesn't say that the script must be a **direct** subclass of EditorPlugin (and an indirect subclass works fine in GDScript), I interpret this behavior as a Godot bug.

### Steps to reproduce

See above

### Minimal reproduction project

[gdext_editor_plugin_test.zip](https://github.com/godotengine/godot/files/13451014/gdext_editor_plugin_test.zip)
}
#endif
		if (available_drivers.is_empty()) {
			OS::get_singleton()->print("Unknown renderer name '%s', aborting.\n", rendering_method.utf8().get_data());
			goto error;
		}
		for (int i = 0; i < available_drivers.size(); i++) {
			if (rendering_driver == available_drivers[i]) {
				valid_combination = true;
				break;
			}
		}
		if (!valid_combination) {
			OS::get_singleton()->print("Invalid renderer/driver combination '%s' and '%s', aborting. %s only supports the following drivers ", rendering_method.utf8().get_data(), rendering_driver.utf8().get_data(), rendering_method.utf8().get_data());
			for (int d = 0; d < available_drivers.size(); d++) {
				OS::get_singleton()->print("'%s', ", available_drivers[d].utf8().get_data());
			}
			OS::get_singleton()->print(".\n");
			goto error;
		}
	}
	default_renderer = renderer_hints.get_slice(",", 0);
	GLOBAL_DEF_RST_BASIC(PropertyInfo(Variant::STRING, "rendering/renderer/rendering_method", PROPERTY_HINT_ENUM, renderer_hints), default_renderer);
	GLOBAL_DEF_RST_BASIC("rendering/renderer/rendering_method.mobile", default_renderer_mobile);
	GLOBAL_DEF_RST_BASIC("rendering/renderer/rendering_method.web", "gl_compatibility"); 
	
	if (rendering_method.is_empty()) {
		rendering_method = GLOBAL_GET("rendering/renderer/rendering_method");
	}
	if (rendering_driver.is_empty()) {