### 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

‮
ERR_FAIL_NULL(p_identifier);
	p_identifier->set_datatype(p_identifier_datatype);
	Error err = OK;
	GDScript *scr = GDScriptCache::get_shallow_script(p_identifier_datatype.script_path, err).ptr();
	ERR_FAIL_COND_MSG(err != OK, vformat(R"(Error while getting cache for script "%s".)", p_identifier_datatype.script_path));
	scr = scr->find_class(p_identifier_datatype.class_type->fqcn);
	p_identifier->reduced_value = scr;
	p_identifier->is_constant = true;
}
void GDScriptAnalyzer::reduce_identifier_from_base(GDScriptParser::IdentifierNode *p_identifier, GDScriptParser::DataType *p_base) {