### 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.
const GDScript *current = this;
	while (current) {
		for (const KeyValue<StringName, GDScriptFunction *> &E : current->member_functions) {
			GDScriptFunction *func = E.value;
			MethodInfo mi;
			mi.name = E.key;
			if (func->is_static()) {
				mi.flags |= METHOD_FLAG_STATIC;
			}
			for (int i = 0; i < func->get_argument_count(); i++) {
				PropertyInfo arginfo = func->get_argument_type(i);
#ifdef TOOLS_ENABLED
				arginfo.name = func->get_argument_name(i);
#endif
				mi.arguments.push_back(arginfo);
			}
#ifdef TOOLS_ENABLED
			mi.default_arguments.append_array(func->get_default_arg_values());
#endif
			mi.return_val = func->get_return_type();
			r_list->push_back(mi);
		}
		if (!p_include_base) {
			return;
		}
		current = current->_base;
	}
}
void GDScript::get_script_method_list(List<MethodInfo> *r_list) const {