### 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
native_base = export_type.script_type->get_instance_base_type();
				}
				if (class_name == StringName()) {
					Ref<Script> script = ResourceLoader::load(export_type.script_path, SNAME("Script"));
					if (script.is_valid()) {
						class_name = script->get_language()->get_global_class_name(export_type.script_path);
						native_base = script->get_instance_base_type();
					}
				}
				if (class_name != StringName() && native_base != StringName() && ClassDB::is_parent_class(native_base, SNAME("Resource"))) {
					variable->export_info.type = Variant::OBJECT;
					variable->export_info.hint = PROPERTY_HINT_RESOURCE_TYPE;
					variable->export_info.hint_string = class_name;
				}
			} break;
			case GDScriptParser::DataType::ENUM: {
				variable->export_info.type = Variant::INT;
				variable->export_info.hint = PROPERTY_HINT_ENUM;
				String enum_hint_string;
				bool first = true;
				for (const KeyValue<StringName, int64_t> &E : export_type.enum_values) {
					if (!first) {
						enum_hint_string += ",";
					} else {
						first = false;
					}
					enum_hint_string += E.key.operator String().capitalize().xml_escape();
					enum_hint_string += ":";
					enum_hint_string += String::num_int64(E.value).xml_escape();
				}