### Godot version

4.0 rc1

### System information

Windows 11, GTX 1080Ti, Vulkan

### Issue description

Automplete can't find any variables and methods on custom classes when the nodes are loaded with `@onready`:

simple_rotate.gd:
```gdscript
extends Node2D
class_name SimpleRotate

@export var shouldRotate : bool = true
```

machine.gd:
```gdscript
@onready var wheel1 : SimpleRotate = $Wheel

func start_motor():
	wheel1.sho... # Doesn't autocomplete, it can't find shouldRotate 
```

If I add another cast like below, autocomplete does work:
machine.gd:
```gdscript
@onready var wheel1 : SimpleRotate = $Wheel as SimpleRotate

func start_motor():
	wheel1.shouldRotate = true # Autocomplete works
```

To make things even weirder, it does work if I make Wheel into a unique name and access it using %:
machine.gd:
```gdscript
@onready var wheel1 : SimpleRotate = $"%Wheel"

func start_motor():
	wheel1.shouldRotate = true # Autocomplete works
```


### Steps to reproduce

- Create a script with a class_name
- Add that script to a node
- Create another script referencing the node with the type of the script
- Try to let automcomplete find any methods or variables on the script with the class_name
- Notice that it fails

### Minimal reproduction project

N/A
ScriptLanguage::CodeCompletionOption option(*kw, ScriptLanguage::CODE_COMPLETION_KIND_PLAIN_TEXT);
		r_result.insert(option.display, option);
		kw++;
	}
	static const char *_keywords_with_space[] = {
		"and", "not", "or", "in", "as", "class", "class_name", "extends", "is", "func", "signal", "await",
		"const", "enum", "static", "var", "if", "elif", "else", "for", "match", "when", "while",
		nullptr
	};
	const char **kws = _keywords_with_space;
	while (*kws) {
		ScriptLanguage::CodeCompletionOption option(*kws, ScriptLanguage::CODE_COMPLETION_KIND_PLAIN_TEXT);
		option.insert_text += " ";
		r_result.insert(option.display, option);
		kws++;
	}
	static const char *_keywords_with_args[] = {
		"assert", "preload",
		nullptr
	};
	const char **kwa = _keywords_with_args;
	while (*kwa) {
		ScriptLanguage::CodeCompletionOption option(*kwa, ScriptLanguage::CODE_COMPLETION_KIND_FUNCTION);
		option.insert_text += "(";
		r_result.insert(option.display, option);
		kwa++;
	}
	List<StringName> utility_func_names;
	Variant::get_utility_function_list(&utility_func_names);
	for (List<StringName>::Element *E = utility_func_names.front(); E; E = E->next()) {