### 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_identifier->get_datatype().has_no_type()) {
		return;
	}
	GDScriptParser::DataType base;
	if (p_base == nullptr) {
		base = type_from_metatype(parser->current_class->get_datatype());
	} else {
		base = *p_base;
	}
	const StringName &name = p_identifier->name;
	if (base.kind == GDScriptParser::DataType::ENUM) {
		if (base.is_meta_type) {
			if (base.enum_values.has(name)) {
				p_identifier->set_datatype(type_from_metatype(base));
				p_identifier->is_constant = true;
				p_identifier->reduced_value = base.enum_values[name];
				return;
			}
			
			return;
		} else {
			push_error(R"(Cannot get property from enum value.)", p_identifier);
			return;
		}
	}
	if (base.kind == GDScriptParser::DataType::BUILTIN) {
		if (base.is_meta_type) {