### Godot version

4.2 f5696c3

### System information

Windows 10 x64

### Issue description

![image](https://github.com/godotengine/godot/assets/2223172/7ad0e3b6-9599-4f7b-a07c-da54779e647a)


### Steps to reproduce

1. Add node
2. Attach a built-in script
3. Add child node
4. Add script to the child node
5. In some method write `get_parent().bui`

### Minimal reproduction project

N/A
if ("Variant" == p_symbol) {
		r_result.type = ScriptLanguage::LOOKUP_RESULT_CLASS;
		r_result.class_name = "Variant";
		return OK;
	}
	if ("PI" == p_symbol || "TAU" == p_symbol || "INF" == p_symbol || "NAN" == p_symbol) {
		r_result.type = ScriptLanguage::LOOKUP_RESULT_CLASS_CONSTANT;
		r_result.class_name = "@GDScript";
		r_result.class_member = p_symbol;
		return OK;
	}
	GDScriptParser parser;
	parser.parse(p_code, p_path, true);
	GDScriptParser::CompletionContext context = parser.get_completion_context();
	context.base = p_owner;
	
	if (context.type != GDScriptParser::COMPLETION_ATTRIBUTE) {
		
		
		if (GDScriptUtilityFunctions::function_exists(p_symbol) || "assert" == p_symbol || "preload" == p_symbol) {
			r_result.type = ScriptLanguage::LOOKUP_RESULT_CLASS_METHOD;
			r_result.class_name = "@GDScript";
			r_result.class_member = p_symbol;
			return OK;
		}
	}
	GDScriptAnalyzer analyzer(&parser);
	analyzer.analyze();
	if (context.current_class && context.current_class->extends.size() > 0) {
		bool success = false;