### 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.
Object *obj = p_variant;
	if (obj == nullptr || obj->get_instance_id().is_null()) {
		return nullptr;
	}
	return Object::cast_to<GDScript>(obj);
}
void GDScript::_get_dependencies(RBSet<GDScript *> &p_dependencies, const GDScript *p_except) {
	if (p_dependencies.has(this)) {
		return;
	}
	p_dependencies.insert(this);
	for (const KeyValue<StringName, GDScriptFunction *> &E : member_functions) {
		if (E.value == nullptr) {
			continue;
		}
		for (const Variant &V : E.value->constants) {
			GDScript *scr = _get_gdscript_from_variant(V);
			if (scr != nullptr && scr != p_except) {
				scr->_get_dependencies(p_dependencies, p_except);
			}
		}