### 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

‮
assignment->assignee = p_previous_operand;
	assignment->assigned_value = parse_expression(false);
	if (assignment->assigned_value == nullptr) {
		push_error(R"(Expected an expression after "=".)");
	}
	complete_extents(assignment);
#ifdef DEBUG_ENABLED
	if (source_variable != nullptr) {
		if (has_operator && source_variable->assignments == 0) {
			push_warning(assignment, GDScriptWarning::UNASSIGNED_VARIABLE_OP_ASSIGN, source_variable->identifier->name);
		}
		source_variable->assignments += 1;
	}
#endif
	return assignment;
}
GDScriptParser::ExpressionNode *GDScriptParser::parse_await(ExpressionNode *p_previous_operand, bool p_can_assign) {
	AwaitNode *await = alloc_node<AwaitNode>();
	ExpressionNode *element = parse_precedence(PREC_AWAIT, false);
	if (element == nullptr) {
		push_error(R"(Expected signal or coroutine after "await".)");
	}
	await->to_await = element;
	complete_extents(await);
	if (current_function) { 
		current_function->is_coroutine = true;
	}
	return await;
}
GDScriptParser::ExpressionNode *GDScriptParser::parse_array(ExpressionNode *p_previous_operand, bool p_can_assign) {