### 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
switch (mode) {
			case BRIEF:
				p_brief = (p_brief.length() == 0) ? doc_line : p_brief + line_join + doc_line;
				break;
			case DESC:
				p_desc = (p_desc.length() == 0) ? doc_line : p_desc + line_join + doc_line;
				break;
			case TUTORIALS:
				p_tutorials.append(Pair<String, String>(title, link));
				break;
			case DONE:
				break;
		}
	}
	if (current_class->members.size() > 0) {
		const ClassNode::Member &m = current_class->members[0];
		int first_member_line = m.get_line();
		if (first_member_line == line) {
			p_brief = "";
			p_desc = "";
			p_tutorials.clear();
		}
	}
}
#endif 
GDScriptParser::ParseRule *GDScriptParser::get_rule(GDScriptTokenizer::Token::Type p_token_type) {
	
	
	
	static ParseRule rules[] = {