### 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

‮
mark_node_unsafe(p_assignment);
				if (assignee_is_hard) {
					if (is_type_compatible(op_type, assignee_type)) {
						
						p_assignment->use_conversion_assign = true;
					} else {
						
						push_error(vformat(R"(Value of type "%s" cannot be assigned to a variable of type "%s".)", assigned_value_type.to_string(), assignee_type.to_string()), p_assignment->assigned_value);
					}
				} else {
					
					downgrades_assignee = true;
				}
			}
		}
	}
	if (downgrades_assignee) {
		downgrade_node_type_source(p_assignment->assignee);
	}
	if (downgrades_assigned) {
		downgrade_node_type_source(p_assignment->assigned_value);
	}
#ifdef DEBUG_ENABLED
	if (assignee_type.is_hard_type() && assignee_type.builtin_type == Variant::INT && assigned_value_type.builtin_type == Variant::FLOAT) {
		parser->push_warning(p_assignment->assigned_value, GDScriptWarning::NARROWING_CONVERSION);
	}
#endif
}
void GDScriptAnalyzer::reduce_await(GDScriptParser::AwaitNode *p_await) {