### 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)
Node *n = nullptr;
	if (ResourceLoader::get_resource_type(p_path) == "PackedScene") {
		
		Ref<PackedScene> scn;
		scn.instantiate();
		scn->set_path(p_path);
		scn->reload_from_file();
		ERR_FAIL_COND_V_MSG(!scn.is_valid(), nullptr, vformat("Can't autoload: %s.", p_path));
		if (scn.is_valid()) {
			n = scn->instantiate();
		}
	} else {
		Ref<Resource> res = ResourceLoader::load(p_path);
		ERR_FAIL_COND_V_MSG(res.is_null(), nullptr, vformat("Can't autoload: %s.", p_path));
		Ref<Script> scr = res;
		if (scr.is_valid()) {
			StringName ibt = scr->get_instance_base_type();
			bool valid_type = ClassDB::is_parent_class(ibt, "Node");
			ERR_FAIL_COND_V_MSG(!valid_type, nullptr, vformat("Script does not inherit from Node: %s.", p_path));
			Object *obj = ClassDB::instantiate(ibt);
			ERR_FAIL_NULL_V_MSG(obj, nullptr, vformat("Cannot instance script for Autoload, expected 'Node' inheritance, got: %s.", ibt));
			n = Object::cast_to<Node>(obj);
			n->set_script(scr);
		}
	}
	ERR_FAIL_NULL_V_MSG(n, nullptr, vformat("Path in Autoload not a node or script: %s.", p_path));
	return n;
}
void EditorAutoloadSettings::update_autoload() {