### 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.
break;
						}
						String subpath = subclass->extends_path;
						if (subpath.is_relative_path()) {
							subpath = path.get_base_dir().path_join(subpath).simplify_path();
						}
						if (OK != subparser.parse(subsource, subpath, false)) {
							break;
						}
						path = subpath;
						subclass = subparser.get_tree();
						while (extend_classes.size() > 0) {
							bool found = false;
							for (int i = 0; i < subclass->members.size(); i++) {
								if (subclass->members[i].type != GDScriptParser::ClassNode::Member::CLASS) {
									continue;
								}
								const GDScriptParser::ClassNode *inner_class = subclass->members[i].m_class;
								if (inner_class->identifier->name == extend_classes[0]) {
									extend_classes.remove_at(0);
									found = true;
									subclass = inner_class;
									break;
								}
							}
							if (!found) {
								subclass = nullptr;
								break;
							}
						}