### 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.
}
	
	for (int i = 1; result != nullptr && i < class_names.size(); i++) {
		String current_name = class_names[i];
		if (HashMap<StringName, Ref<GDScript>>::Iterator E = result->subclasses.find(current_name)) {
			result = E->value.ptr();
		} else {
			
			return nullptr;
		}
	}
	return result;
}
bool GDScript::has_class(const GDScript *p_script) {
	String fqn = p_script->fully_qualified_name;
	if (fully_qualified_name.is_empty() && fqn.get_slice("::", 0).is_empty()) {
		return p_script == this;
	} else if (fqn.begins_with(fully_qualified_name)) {
		return p_script == find_class(fqn.trim_prefix(fully_qualified_name));
	}
	return false;
}
GDScript *GDScript::get_root_script() {
	GDScript *result = this;
	while (result->_owner) {
		result = result->_owner;
	}
	return result;
}
RBSet<GDScript *> GDScript::get_dependencies() {