### 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

‮
#endif
				result_type.kind = GDScriptParser::DataType::VARIANT;
				mark_node_unsafe(p_subscript);
			}
		}
		if (!valid) {
			push_error(vformat(R"(Cannot find member "%s" in base "%s".)", p_subscript->attribute->name, type_from_metatype(base_type).to_string()), p_subscript->attribute);
			result_type.kind = GDScriptParser::DataType::VARIANT;
		}
	} else {
		if (p_subscript->index == nullptr) {
			return;
		}
		reduce_expression(p_subscript->index);
		if (p_subscript->base->is_constant && p_subscript->index->is_constant) {
			
			bool valid = false;
			Variant value = p_subscript->base->reduced_value.get(p_subscript->index->reduced_value, &valid);
			if (!valid) {
				push_error(vformat(R"(Cannot get index "%s" from "%s".)", p_subscript->index->reduced_value, p_subscript->base->reduced_value), p_subscript->index);
				result_type.kind = GDScriptParser::DataType::VARIANT;
			} else {
				p_subscript->is_constant = true;
				p_subscript->reduced_value = value;
				result_type = type_from_variant(value, p_subscript);
			}
		} else {
			GDScriptParser::DataType base_type = p_subscript->base->get_datatype();
			GDScriptParser::DataType index_type = p_subscript->index->get_datatype();
			if (base_type.is_variant()) {