### 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

‮
GDScriptParser::Node *source = nullptr;
	switch (identifier->source) {
		case GDScriptParser::IdentifierNode::MEMBER_VARIABLE: {
			source = identifier->variable_source;
		} break;
		case GDScriptParser::IdentifierNode::FUNCTION_PARAMETER: {
			source = identifier->parameter_source;
		} break;
		case GDScriptParser::IdentifierNode::LOCAL_VARIABLE: {
			source = identifier->variable_source;
		} break;
		case GDScriptParser::IdentifierNode::LOCAL_ITERATOR: {
			source = identifier->bind_source;
		} break;
		default:
			break;
	}
	if (source == nullptr) {
		return;
	}
	GDScriptParser::DataType datatype;
	datatype.kind = GDScriptParser::DataType::VARIANT;
	source->set_datatype(datatype);
}
void GDScriptAnalyzer::mark_lambda_use_self() {
	for (GDScriptParser::LambdaNode *lambda : lambda_stack) {
		lambda->use_self = true;
	}
}
bool GDScriptAnalyzer::class_exists(const StringName &p_class) const {