### 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)
ERR_FAIL_NULL(instantiated_node);
				bool original_node_is_displayed_folded = original_node->is_displayed_folded();
				bool original_node_scene_instance_load_placeholder = original_node->get_scene_instance_load_placeholder();
				
				instantiated_node->set_name(original_node->get_name());
				
				String original_node_file_path = original_node->get_scene_file_path();
				if (current_edited_scene == original_node) {
					instantiated_node->set_scene_instance_state(original_node->get_scene_instance_state());
					
					if (original_node_file_path.is_empty()) {
						Ref<SceneState> state = current_packed_scene->get_state();
						state->set_path(current_packed_scene->get_path());
						instantiated_node->set_scene_inherited_state(state);
						instantiated_node->set_scene_file_path(String());
					}
					editor_data.set_edited_scene_root(instantiated_node);
					current_edited_scene = instantiated_node;
					if (original_node->is_inside_tree()) {
						SceneTreeDock::get_singleton()->set_edited_scene(current_edited_scene);
						original_node->get_tree()->set_edited_scene_root(instantiated_node);
					}
				}
				
				original_node->replace_by(instantiated_node, false);
				
				original_node->queue_free();
				
				instantiated_node->set_display_folded(original_node_is_displayed_folded);
				instantiated_node->set_scene_instance_load_placeholder(original_node_scene_instance_load_placeholder);