### 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_match_pattern == nullptr) {
		return;
	}
	GDScriptParser::DataType result;
	switch (p_match_pattern->pattern_type) {
		case GDScriptParser::PatternNode::PT_LITERAL:
			if (p_match_pattern->literal) {
				reduce_literal(p_match_pattern->literal);
				result = p_match_pattern->literal->get_datatype();
			}
			break;
		case GDScriptParser::PatternNode::PT_EXPRESSION:
			if (p_match_pattern->expression) {
				GDScriptParser::ExpressionNode *expr = p_match_pattern->expression;
				reduce_expression(expr);
				result = expr->get_datatype();
				if (!expr->is_constant) {
					while (expr && expr->type == GDScriptParser::Node::SUBSCRIPT) {
						GDScriptParser::SubscriptNode *sub = static_cast<GDScriptParser::SubscriptNode *>(expr);
						if (!sub->is_attribute) {
							expr = nullptr;
						} else {
							expr = sub->base;
						}
					}
					if (!expr || expr->type != GDScriptParser::Node::IDENTIFIER) {
						push_error(R"(Expression in match pattern must be a constant expression, an identifier, or an attribute access ("A.B").)", expr);
					}
				}