### 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)
resource_conversion_plugins.push_back(p_plugin);
}
void EditorNode::remove_resource_conversion_plugin(const Ref<EditorResourceConversionPlugin> &p_plugin) {
	resource_conversion_plugins.erase(p_plugin);
}
Vector<Ref<EditorResourceConversionPlugin>> EditorNode::find_resource_conversion_plugin(const Ref<Resource> &p_for_resource) {
	Vector<Ref<EditorResourceConversionPlugin>> ret;
	for (int i = 0; i < resource_conversion_plugins.size(); i++) {
		if (resource_conversion_plugins[i].is_valid() && resource_conversion_plugins[i]->handles(p_for_resource)) {
			ret.push_back(resource_conversion_plugins[i]);
		}
	}
	return ret;
}
void EditorNode::_bottom_panel_raise_toggled(bool p_pressed) {
	top_split->set_visible(!p_pressed);
}
void EditorNode::_update_renderer_color() {
	String rendering_method = renderer->get_selected_metadata();
	if (rendering_method == "forward_plus") {
		renderer->add_theme_color_override("font_color", Color::hex(0x5d8c3fff));
	}
	if (rendering_method == "mobile") {
		renderer->add_theme_color_override("font_color", Color::hex(0xa5557dff));
	}
	if (rendering_method == "gl_compatibility") {
		renderer->add_theme_color_override("font_color", Color::hex(0x5586a4ff));
	}
}
void EditorNode::_renderer_selected(int p_which) {