### 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

‮
result_type.builtin_type = Variant::STRING;
						break;
					
					case Variant::PACKED_VECTOR2_ARRAY:
					case Variant::TRANSFORM2D:
					case Variant::RECT2:
						result_type.builtin_type = Variant::VECTOR2;
						break;
					
					case Variant::RECT2I:
						result_type.builtin_type = Variant::VECTOR2I;
						break;
					
					case Variant::PACKED_VECTOR3_ARRAY:
					case Variant::AABB:
					case Variant::BASIS:
						result_type.builtin_type = Variant::VECTOR3;
						break;
					
					case Variant::TRANSFORM3D:
					case Variant::PROJECTION:
					case Variant::PLANE:
					case Variant::COLOR:
					case Variant::DICTIONARY:
					case Variant::OBJECT:
						result_type.kind = GDScriptParser::DataType::VARIANT;
						result_type.type_source = GDScriptParser::DataType::UNDETECTED;
						break;
					
					case Variant::ARRAY: