### Godot version

4.0-rc1

### System information

Windows 10

### Issue description

The code: `@export @onready var camera_system : Node3D`

Is throwing: `Line 5:The "@onready" annotation will make the default value to be set after the "@export" takes effect and will override it. (Warning treated as error.)` and is crashing the game.

Unchecking "Treat Warning as Errors" seems to have no effect:

![imagen](https://user-images.githubusercontent.com/248383/217900756-8e214c40-68fb-4fb2-8509-a1e689725930.png)

![imagen](https://user-images.githubusercontent.com/248383/217901253-3b758ebc-48e9-40fe-8d77-16fce7cbae88.png)


### Steps to reproduce

- Write `@export @onready var some_var : Node3D`
- In Project Settings, uncheck `Treat Warning as Errors`
- Try to run the project, a `Parser Error` will be thrown.

### Minimal reproduction project

It's as simple as adding one line of code, so I'm not sure a MRP is needed.
#ifdef TOOLS_ENABLED
	bool cyclic_error = false;
	_update_exports(&cyclic_error);
	if (cyclic_error) {
		return;
	}
	HashSet<ObjectID> copy = inheriters_cache; 
	for (const ObjectID &E : copy) {
		Object *id = ObjectDB::get_instance(E);
		GDScript *s = Object::cast_to<GDScript>(id);
		if (!s) {
			continue;
		}
		s->update_exports();
	}
#endif
}
String GDScript::_get_debug_path() const {
	if (is_built_in() && !get_name().is_empty()) {
		return vformat("%s(%s)", get_name(), get_script_path());
	} else {
		return get_script_path();
	}
}
Error GDScript::reload(bool p_keep_state) {