### 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
if (builtin_types.is_empty()) {
		builtin_types["bool"] = Variant::BOOL;
		builtin_types["int"] = Variant::INT;
		builtin_types["float"] = Variant::FLOAT;
		builtin_types["String"] = Variant::STRING;
		builtin_types["Vector2"] = Variant::VECTOR2;
		builtin_types["Vector2i"] = Variant::VECTOR2I;
		builtin_types["Rect2"] = Variant::RECT2;
		builtin_types["Rect2i"] = Variant::RECT2I;
		builtin_types["Transform2D"] = Variant::TRANSFORM2D;
		builtin_types["Vector3"] = Variant::VECTOR3;
		builtin_types["Vector3i"] = Variant::VECTOR3I;
		builtin_types["Vector4"] = Variant::VECTOR4;
		builtin_types["Vector4i"] = Variant::VECTOR4I;
		builtin_types["AABB"] = Variant::AABB;
		builtin_types["Plane"] = Variant::PLANE;
		builtin_types["Quaternion"] = Variant::QUATERNION;
		builtin_types["Basis"] = Variant::BASIS;
		builtin_types["Transform3D"] = Variant::TRANSFORM3D;
		builtin_types["Projection"] = Variant::PROJECTION;
		builtin_types["Color"] = Variant::COLOR;
		builtin_types["RID"] = Variant::RID;
		builtin_types["Object"] = Variant::OBJECT;
		builtin_types["StringName"] = Variant::STRING_NAME;
		builtin_types["NodePath"] = Variant::NODE_PATH;
		builtin_types["Dictionary"] = Variant::DICTIONARY;
		builtin_types["Callable"] = Variant::CALLABLE;