### 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)
opening_prev = false;
		if (prev != -1) {
			_set_current_scene(prev);
			editor_data.remove_scene(idx);
		}
		return ERR_FILE_NOT_FOUND;
	}
	dependency_errors.erase(lpath); 
	for (KeyValue<String, HashSet<String>> &E : dependency_errors) {
		String txt = vformat(TTR("Scene '%s' has broken dependencies:"), E.key) + "\n";
		for (const String &F : E.value) {
			txt += "\t" + F + "\n";
		}
		add_io_error(txt);
	}
	if (ResourceCache::has(lpath)) {
		
		Ref<PackedScene> ps = ResourceCache::get_ref(lpath);
		if (ps.is_valid()) {
			ps->replace_state(sdata->get_state());
			ps->set_last_modified_time(sdata->get_last_modified_time());
			sdata = ps;
		}
	} else {
		sdata->set_path(lpath, true); 
	}
	Node *new_scene = sdata->instantiate(p_set_inherited ? PackedScene::GEN_EDIT_STATE_MAIN_INHERITED : PackedScene::GEN_EDIT_STATE_MAIN);
	if (!new_scene) {
		sdata.unref();
		_dialog_display_load_error(lpath, ERR_FILE_CORRUPT);