### Godot version

3b086aa06

### System information

ArchLinux x11

### Issue description

```gdscript
extends Node

@export_group("My Properties")
@export var number = 3
@export var string = ""

@export_group("Prefixed Properties", "prefix_")
@export var prefix_number = 3
@export var prefix_string = ""

@export_group("", "")
@export var ungrouped_number = 3
```

![image](https://user-images.githubusercontent.com/70787919/214983963-528c415b-745b-47fc-9777-36ebe31a3060.png)


### Steps to reproduce

- create script
- @export_group
- go inspector

### Minimal reproduction project

‮
current_class->extends_used = true;
	int chain_index = 0;
	if (match(GDScriptTokenizer::Token::LITERAL)) {
		if (previous.literal.get_type() != Variant::STRING) {
			push_error(vformat(R"(Only strings or identifiers can be used after "extends", found "%s" instead.)", Variant::get_type_name(previous.literal.get_type())));
		}
		current_class->extends_path = previous.literal;
		if (!match(GDScriptTokenizer::Token::PERIOD)) {
			return;
		}
	}
	make_completion_context(COMPLETION_INHERIT_TYPE, current_class, chain_index++);
	if (!consume(GDScriptTokenizer::Token::IDENTIFIER, R"(Expected superclass name after "extends".)")) {
		return;
	}
	current_class->extends.push_back(previous.literal);
	while (match(GDScriptTokenizer::Token::PERIOD)) {
		make_completion_context(COMPLETION_INHERIT_TYPE, current_class, chain_index++);
		if (!consume(GDScriptTokenizer::Token::IDENTIFIER, R"(Expected superclass name after ".".)")) {
			return;
		}
		current_class->extends.push_back(previous.literal);
	}
}
template <class T>
void GDScriptParser::parse_class_member(T *(GDScriptParser::*p_parse_function)(), AnnotationInfo::TargetKind p_target, const String &p_member_kind) {
	advance();
#ifdef TOOLS_ENABLED
	int doc_comment_line = previous.start_line - 1;
#endif