### 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 (GLOBAL_GET("debug/settings/stdout/print_fps") || print_fps) {
		
		switch (window_vsync_mode) {
			case DisplayServer::VSyncMode::VSYNC_DISABLED:
				print_line("Requested V-Sync mode: Disabled");
				break;
			case DisplayServer::VSyncMode::VSYNC_ENABLED:
				print_line("Requested V-Sync mode: Enabled - FPS will likely be capped to the monitor refresh rate.");
				break;
			case DisplayServer::VSyncMode::VSYNC_ADAPTIVE:
				print_line("Requested V-Sync mode: Adaptive");
				break;
			case DisplayServer::VSyncMode::VSYNC_MAILBOX:
				print_line("Requested V-Sync mode: Mailbox");
				break;
		}
	}
	if (OS::get_singleton()->_render_thread_mode == OS::RENDER_SEPARATE_THREAD) {
		WARN_PRINT("The Multi-Threaded rendering thread model is experimental, and has known issues which can lead to project crashes. Use the Single-Safe option in the project settings instead.");
	}
	
	{
		GLOBAL_DEF_RST_NOVAL("input_devices/pen_tablet/driver", "");
		GLOBAL_DEF_RST_NOVAL(PropertyInfo(Variant::STRING, "input_devices/pen_tablet/driver.windows", PROPERTY_HINT_ENUM, "wintab,winink"), "");
	}
	if (tablet_driver.is_empty()) { 
		tablet_driver = GLOBAL_GET("input_devices/pen_tablet/driver");
		if (tablet_driver.is_empty()) {
			tablet_driver = DisplayServer::get_singleton()->tablet_get_driver_name(0);