### 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

‮
case ClassNode::Member::CLASS:
				print_class(m.m_class);
				break;
			case ClassNode::Member::VARIABLE:
				print_variable(m.variable);
				break;
			case ClassNode::Member::CONSTANT:
				print_constant(m.constant);
				break;
			case ClassNode::Member::SIGNAL:
				print_signal(m.signal);
				break;
			case ClassNode::Member::FUNCTION:
				print_function(m.function);
				break;
			case ClassNode::Member::ENUM:
				print_enum(m.m_enum);
				break;
			case ClassNode::Member::ENUM_VALUE:
				break; 
			case ClassNode::Member::GROUP:
				break; 
			case ClassNode::Member::UNDEFINED:
				push_line("<unknown member>");
				break;
		}
	}
	decrease_indent();
}
void GDScriptParser::TreePrinter::print_constant(ConstantNode *p_constant) {