### 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)
create_menu = true;
	}
	if (create_menu) {
		Point2i pos = tx->get_line_column_at_pos(local_pos);
		int row = pos.y;
		int col = pos.x;
		tx->set_move_caret_on_right_click_enabled(EDITOR_GET("text_editor/behavior/navigation/move_caret_on_right_click"));
		int caret_clicked = -1;
		if (tx->is_move_caret_on_right_click_enabled()) {
			if (tx->has_selection()) {
				for (int i = 0; i < tx->get_caret_count(); i++) {
					int from_line = tx->get_selection_from_line(i);
					int to_line = tx->get_selection_to_line(i);
					int from_column = tx->get_selection_from_column(i);
					int to_column = tx->get_selection_to_column(i);
					if (row >= from_line && row <= to_line && (row != from_line || col >= from_column) && (row != to_line || col <= to_column)) {
						
						caret_clicked = i;
						break;
					}
				}
			}
			if (caret_clicked < 0) {
				tx->deselect();
				tx->remove_secondary_carets();
				caret_clicked = 0;
				tx->set_caret_line(row, false, false);
				tx->set_caret_column(col);
			}
		}