### 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

‮
if (!p_preload->path) {
		return;
	}
	reduce_expression(p_preload->path);
	if (!p_preload->path->is_constant) {
		push_error("Preloaded path must be a constant string.", p_preload->path);
		return;
	}
	if (p_preload->path->reduced_value.get_type() != Variant::STRING) {
		push_error("Preloaded path must be a constant string.", p_preload->path);
	} else {
		p_preload->resolved_path = p_preload->path->reduced_value;
		
		if (p_preload->resolved_path.is_relative_path()) {
			p_preload->resolved_path = parser->script_path.get_base_dir().path_join(p_preload->resolved_path);
		}
		p_preload->resolved_path = p_preload->resolved_path.simplify_path();
		if (!ResourceLoader::exists(p_preload->resolved_path)) {
			Ref<FileAccess> file_check = FileAccess::create(FileAccess::ACCESS_RESOURCES);
			if (file_check->file_exists(p_preload->resolved_path)) {
				push_error(vformat(R"(Preload file "%s" has no resource loaders (unrecognized file extension).)", p_preload->resolved_path), p_preload->path);
			} else {
				push_error(vformat(R"(Preload file "%s" does not exist.)", p_preload->resolved_path), p_preload->path);
			}
		} else {
			
			
			
			if (ResourceLoader::get_resource_type(p_preload->resolved_path) == "GDScript") {
				Error err = OK;