### 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
if (!p_only_functions && p_context.current_suite) {
		
		_find_identifiers_in_suite(p_context.current_suite, r_result);
	}
	if (p_context.current_class) {
		_find_identifiers_in_class(p_context.current_class, p_only_functions, (!p_context.current_function || p_context.current_function->is_static), false, r_result, p_recursion_depth);
	}
	List<StringName> functions;
	GDScriptUtilityFunctions::get_function_list(&functions);
	for (const StringName &E : functions) {
		MethodInfo function = GDScriptUtilityFunctions::get_function_info(E);
		ScriptLanguage::CodeCompletionOption option(String(E), ScriptLanguage::CODE_COMPLETION_KIND_FUNCTION);
		if (function.arguments.size() || (function.flags & METHOD_FLAG_VARARG)) {
			option.insert_text += "(";
		} else {
			option.insert_text += "()";
		}
		r_result.insert(option.display, option);
	}
	if (p_only_functions) {
		return;
	}
	_find_built_in_variants(r_result);
	static const char *_keywords[] = {
		"true", "false", "PI", "TAU", "INF", "NAN", "null", "self", "super",
		"break", "breakpoint", "continue", "pass", "return",
		nullptr
	};
	const char **kw = _keywords;
	while (*kw) {