### 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

‮
if (p_source == nullptr && parser->has_class(p_class)) {
		p_source = p_class;
	}
	if (!p_class->resolved_interface) {
		if (!parser->has_class(p_class)) {
			String script_path = p_class->get_datatype().script_path;
			Ref<GDScriptParserRef> parser_ref = get_parser_for(script_path);
			if (parser_ref.is_null()) {
				push_error(vformat(R"(Could not find script "%s".)", script_path), p_source);
				return;
			}
			Error err = parser_ref->raise_status(GDScriptParserRef::PARSED);
			if (err) {
				push_error(vformat(R"(Could not resolve script "%s": %s.)", script_path, error_names[err]), p_source);
				return;
			}
			ERR_FAIL_COND_MSG(!parser_ref->get_parser()->has_class(p_class), R"(Parser bug: Mismatched external parser.)");
			GDScriptAnalyzer *other_analyzer = parser_ref->get_analyzer();
			GDScriptParser *other_parser = parser_ref->get_parser();
			int error_count = other_parser->errors.size();
			other_analyzer->resolve_class_interface(p_class);
			if (other_parser->errors.size() > error_count) {