### 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.
name = p_name;
}
bool GDScriptNativeClass::_get(const StringName &p_name, Variant &r_ret) const {
	bool ok;
	int64_t v = ClassDB::get_integer_constant(name, p_name, &ok);
	if (ok) {
		r_ret = v;
		return true;
	} else {
		return false;
	}
}
void GDScriptNativeClass::_bind_methods() {
	ClassDB::bind_method(D_METHOD("new"), &GDScriptNativeClass::_new);
}
Variant GDScriptNativeClass::_new() {
	Object *o = instantiate();
	ERR_FAIL_COND_V_MSG(!o, Variant(), "Class type: '" + String(name) + "' is not instantiable.");
	RefCounted *rc = Object::cast_to<RefCounted>(o);
	if (rc) {
		return Ref<RefCounted>(rc);
	} else {
		return o;
	}
}
Object *GDScriptNativeClass::instantiate() {