### 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)
return drag_data;
}
Variant EditorNode::drag_files_and_dirs(const Vector<String> &p_paths, Control *p_from) {
	bool has_folder = false;
	bool has_file = false;
	for (int i = 0; i < p_paths.size(); i++) {
		bool is_folder = p_paths[i].ends_with("/");
		has_folder |= is_folder;
		has_file |= !is_folder;
	}
	int max_rows = 6;
	int num_rows = p_paths.size() > max_rows ? max_rows - 1 : p_paths.size(); 
	VBoxContainer *vbox = memnew(VBoxContainer);
	for (int i = 0; i < num_rows; i++) {
		HBoxContainer *hbox = memnew(HBoxContainer);
		TextureRect *icon = memnew(TextureRect);
		Label *label = memnew(Label);
		if (p_paths[i].ends_with("/")) {
			label->set_text(p_paths[i].substr(0, p_paths[i].length() - 1).get_file());
			icon->set_texture(theme->get_icon(SNAME("Folder"), EditorStringName(EditorIcons)));
		} else {
			label->set_text(p_paths[i].get_file());
			icon->set_texture(theme->get_icon(SNAME("File"), EditorStringName(EditorIcons)));
		}
		icon->set_stretch_mode(TextureRect::STRETCH_KEEP_CENTERED);
		icon->set_size(Size2(16, 16));
		hbox->add_child(icon);
		hbox->add_child(label);
		vbox->add_child(hbox);
	}