### 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)
const bool using_single_quotes = EDITOR_GET("text_editor/completion/use_single_quotes");
	String escaped = str.c_escape();
	
	
	if (!using_single_quotes) {
		escaped = escaped.replace("\\'", "\'");
	}
	return escaped.quote(using_single_quotes ? "'" : "\"");
}
static String _get_dropped_resource_line(const Ref<Resource> &p_resource, bool p_create_field) {
	const String &path = p_resource->get_path();
	const bool is_script = ClassDB::is_parent_class(p_resource->get_class(), "Script");
	if (!p_create_field) {
		return vformat("preload(%s)", _quote_drop_data(path));
	}
	String variable_name = p_resource->get_name();
	if (variable_name.is_empty()) {
		variable_name = path.get_file().get_basename();
	}
	if (is_script) {
		variable_name = variable_name.to_pascal_case().validate_identifier();
	} else {
		variable_name = variable_name.to_snake_case().to_upper().validate_identifier();
	}
	return vformat("const %s = preload(%s)", variable_name, _quote_drop_data(path));
}
void ScriptTextEditor::drop_data_fw(const Point2 &p_point, const Variant &p_data, Control *p_from) {