### 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
push_text("Class ");
	if (p_class->identifier == nullptr) {
		push_text("<unnamed>");
	} else {
		print_identifier(p_class->identifier);
	}
	if (p_class->extends_used) {
		bool first = true;
		push_text(" Extends ");
		if (!p_class->extends_path.is_empty()) {
			push_text(vformat(R"("%s")", p_class->extends_path));
			first = false;
		}
		for (int i = 0; i < p_class->extends.size(); i++) {
			if (!first) {
				push_text(".");
			} else {
				first = false;
			}
			push_text(p_class->extends[i]);
		}
	}
	push_line(" :");
	increase_indent();
	for (int i = 0; i < p_class->members.size(); i++) {
		const ClassNode::Member &m = p_class->members[i];
		switch (m.type) {