### 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)
if (!distribution_version.is_empty()) {
		info.push_back(distribution_name + " " + distribution_version);
	} else {
		info.push_back(distribution_name);
	}
#ifdef LINUXBSD_ENABLED
	if (!display_server.is_empty()) {
		info.push_back(display_server);
	}
#endif 
	info.push_back(vformat("%s (%s)", driver_name, rendering_method));
	String graphics;
	if (!device_type_string.is_empty()) {
		graphics = device_type_string + " ";
	}
	graphics += rendering_device_name;
	if (video_adapter_driver_info.size() == 2) { 
		String vad_name = video_adapter_driver_info[0];
		String vad_version = video_adapter_driver_info[1]; 
		if (!vad_version.is_empty()) {
			graphics += vformat(" (%s; %s)", vad_name, vad_version);
		} else {
			graphics += vformat(" (%s)", vad_name);
		}
	}
	info.push_back(graphics);
	info.push_back(vformat("%s (%d Threads)", processor_name, processor_count));
	return String(" - ").join(info);
}
Ref<Texture2D> EditorNode::_file_dialog_get_icon(const String &p_path) {