### 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 (!locale.is_empty() && locale != "en") {
			load_doc_translations(locale);
		}
		{
			Ref<DirAccess> da = DirAccess::open(doc_tool_path);
			ERR_FAIL_COND_V_MSG(da.is_null(), false, "Argument supplied to --doctool must be a valid directory path.");
		}
#ifndef MODULE_MONO_ENABLED
		/
		/
		/
		GLOBAL_DEF("dotnet/project/assembly_name", "");
		GLOBAL_DEF("dotnet/project/solution_directory", "");
		GLOBAL_DEF(PropertyInfo(Variant::INT, "dotnet/project/assembly_reload_attempts", PROPERTY_HINT_RANGE, "1,16,1,or_greater"), 3);
#endif
		Error err;
		DocTools doc;
		doc.generate(gen_flags);
		DocTools docsrc;
		HashMap<String, String> doc_data_classes;
		HashSet<String> checked_paths;
		print_line("Loading docs...");
		for (int i = 0; i < _doc_data_class_path_count; i++) {
			/
			String path = _doc_data_class_paths[i].path;
			if (path.is_relative_path()) {
				path = doc_tool_path.path_join(path);
			}
			String name = _doc_data_class_paths[i].name;