### 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
type->type_chain.push_back(type_element);
	if (match(GDScriptTokenizer::Token::BRACKET_OPEN)) {
		
		type->container_type = parse_type(false); 
		if (type->container_type == nullptr) {
			push_error(R"(Expected type for collection after "[".)");
			complete_extents(type);
			type = nullptr;
		} else if (type->container_type->container_type != nullptr) {
			push_error("Nested typed collections are not supported.");
		}
		consume(GDScriptTokenizer::Token::BRACKET_CLOSE, R"(Expected closing "]" after collection type.)");
		if (type != nullptr) {
			complete_extents(type);
		}
		return type;
	}
	int chain_index = 1;
	while (match(GDScriptTokenizer::Token::PERIOD)) {
		make_completion_context(COMPLETION_TYPE_ATTRIBUTE, type, chain_index++);
		if (consume(GDScriptTokenizer::Token::IDENTIFIER, R"(Expected inner type name after ".".)")) {
			type_element = parse_identifier();
			type->type_chain.push_back(type_element);
		}
	}
	complete_extents(type);
	return type;
}
#ifdef TOOLS_ENABLED
static bool _in_codeblock(String p_line, bool p_already_in, int *r_block_begins = nullptr) {