### 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.
FunctionNode *function = alloc_node<FunctionNode>();
	bool _static = false;
	if (previous.type == GDScriptTokenizer::Token::STATIC) {
		
		if (!consume(GDScriptTokenizer::Token::FUNC, R"(Expected "func" after "static".)")) {
			complete_extents(function);
			return nullptr;
		}
		_static = true;
	}
	make_completion_context(COMPLETION_OVERRIDE_METHOD, function);
	if (!consume(GDScriptTokenizer::Token::IDENTIFIER, R"(Expected function name after "func".)")) {
		complete_extents(function);
		return nullptr;
	}
	FunctionNode *previous_function = current_function;
	current_function = function;
	function->identifier = parse_identifier();
	function->is_static = _static;
	SuiteNode *body = alloc_node<SuiteNode>();
	SuiteNode *previous_suite = current_suite;
	current_suite = body;
	push_multiline(true);
	consume(GDScriptTokenizer::Token::PARENTHESIS_OPEN, R"(Expected opening "(" after function name.)");
	parse_function_signature(function, body, "function");
	current_suite = previous_suite;
	function->body = parse_suite("function declaration", body);
	current_function = previous_function;