### Godot version

v4.0.beta14.official [28a24639c]

### System information

MacOS 12.6.2

### Issue description

Beta 14 throws an error for custom `@icon`, e.g.
```
class_name StateMachine extends Node

@icon("res://assets/icons/state_machine.svg")
```
> Annotation "`@icon`" is not allowed in this level.

In beta 13 and before that worked fine.

### Steps to reproduce

1. Add a custom `@icon` in a custom node script.
2. Error message: Annotation "`@icon`" is not allowed in this level.

There are possibly other errors because a `class_name` node is now not recognized if extended by other classes, but they should resolve if `@icon` is removed.

### Minimal reproduction project

N/A
AnnotationNode *annotation = const_cast<AnnotationNode *>(p_annotation);
	annotation->export_info.name = annotation->resolved_arguments[0];
	switch (t_usage) {
		case PROPERTY_USAGE_CATEGORY: {
			annotation->export_info.usage = t_usage;
		} break;
		case PROPERTY_USAGE_GROUP: {
			annotation->export_info.usage = t_usage;
			if (annotation->resolved_arguments.size() == 2) {
				annotation->export_info.hint_string = annotation->resolved_arguments[1];
			}
		} break;
		case PROPERTY_USAGE_SUBGROUP: {
			annotation->export_info.usage = t_usage;
			if (annotation->resolved_arguments.size() == 2) {
				annotation->export_info.hint_string = annotation->resolved_arguments[1];
			}
		} break;
	}
	current_class->add_member_group(annotation);
	return true;
}
bool GDScriptParser::warning_annotations(const AnnotationNode *p_annotation, Node *p_node) {