### 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

‮
HashSet<uint32_t> previously_ignored = parser->ignored_warning_codes;
		for (uint32_t ignored_warning : stmt->ignored_warnings) {
			parser->ignored_warning_codes.insert(ignored_warning);
		}
#endif 
		resolve_node(stmt);
#ifdef DEBUG_ENABLED
		parser->ignored_warning_codes = previously_ignored;
#endif 
		decide_suite_type(p_suite, stmt);
	}
}
void GDScriptAnalyzer::resolve_assignable(GDScriptParser::AssignableNode *p_assignable, const char *p_kind) {
	GDScriptParser::DataType type;
	type.kind = GDScriptParser::DataType::VARIANT;
	bool is_constant = p_assignable->type == GDScriptParser::Node::CONSTANT;
	GDScriptParser::DataType specified_type;
	bool has_specified_type = p_assignable->datatype_specifier != nullptr;
	if (has_specified_type) {
		specified_type = type_from_metatype(resolve_datatype(p_assignable->datatype_specifier));
		type = specified_type;
	}
	if (p_assignable->initializer != nullptr) {
		reduce_expression(p_assignable->initializer);
		if (p_assignable->initializer->type == GDScriptParser::Node::ARRAY) {
			GDScriptParser::ArrayNode *array = static_cast<GDScriptParser::ArrayNode *>(p_assignable->initializer);
			if ((p_assignable->infer_datatype && array->elements.size() > 0) || (has_specified_type && specified_type.has_container_element_type())) {
				update_array_literal_element_type(specified_type, array);
			}
		}