### 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

‮
bool class_end = false;
	while (!class_end && !is_at_end()) {
		switch (current.type) {
			case GDScriptTokenizer::Token::VAR:
				parse_class_member(&GDScriptParser::parse_variable, AnnotationInfo::VARIABLE, "variable");
				break;
			case GDScriptTokenizer::Token::CONST:
				parse_class_member(&GDScriptParser::parse_constant, AnnotationInfo::CONSTANT, "constant");
				break;
			case GDScriptTokenizer::Token::SIGNAL:
				parse_class_member(&GDScriptParser::parse_signal, AnnotationInfo::SIGNAL, "signal");
				break;
			case GDScriptTokenizer::Token::STATIC:
			case GDScriptTokenizer::Token::FUNC:
				parse_class_member(&GDScriptParser::parse_function, AnnotationInfo::FUNCTION, "function");
				break;
			case GDScriptTokenizer::Token::CLASS:
				parse_class_member(&GDScriptParser::parse_class, AnnotationInfo::CLASS, "class");
				break;
			case GDScriptTokenizer::Token::ENUM:
				parse_class_member(&GDScriptParser::parse_enum, AnnotationInfo::NONE, "enum");
				break;
			case GDScriptTokenizer::Token::ANNOTATION: {
				advance();
				
				AnnotationNode *annotation = parse_annotation(AnnotationInfo::STANDALONE | AnnotationInfo::CLASS_LEVEL);
				if (annotation != nullptr) {
					if (annotation->applies_to(AnnotationInfo::STANDALONE)) {