### 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.
this->_is_tool = true;
	return true;
}
bool GDScriptParser::icon_annotation(const AnnotationNode *p_annotation, Node *p_node) {
	ERR_FAIL_COND_V_MSG(p_node->type != Node::CLASS, false, R"("@icon" annotation can only be applied to classes.)");
	ERR_FAIL_COND_V(p_annotation->resolved_arguments.is_empty(), false);
	ClassNode *p_class = static_cast<ClassNode *>(p_node);
	p_class->icon_path = p_annotation->resolved_arguments[0];
	return true;
}
bool GDScriptParser::onready_annotation(const AnnotationNode *p_annotation, Node *p_node) {
	ERR_FAIL_COND_V_MSG(p_node->type != Node::VARIABLE, false, R"("@onready" annotation can only be applied to class variables.)");
	if (current_class && !ClassDB::is_parent_class(current_class->get_datatype().native_type, SNAME("Node"))) {
		push_error(R"("@onready" can only be used in classes that inherit "Node".)", p_annotation);
	}
	VariableNode *variable = static_cast<VariableNode *>(p_node);
	if (variable->onready) {
		push_error(R"("@onready" annotation can only be used once per variable.)");
		return false;
	}
	variable->onready = true;
	current_class->onready_used = true;
	return true;
}
template <PropertyHint t_hint, Variant::Type t_type>
bool GDScriptParser::export_annotations(const AnnotationNode *p_annotation, Node *p_node) {