### 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

‮
push_text("(");
	switch (p_unary_op->operation) {
		case UnaryOpNode::OP_POSITIVE:
			push_text("+");
			break;
		case UnaryOpNode::OP_NEGATIVE:
			push_text("-");
			break;
		case UnaryOpNode::OP_LOGIC_NOT:
			push_text("NOT");
			break;
		case UnaryOpNode::OP_COMPLEMENT:
			push_text("~");
			break;
	}
	print_expression(p_unary_op->operand);
	
	push_text(")");
}
void GDScriptParser::TreePrinter::print_variable(VariableNode *p_variable) {