### Godot version

4.1.0

### System information

Windows 10, i711800H, Forward+ Vulkan

### Issue description

When using @export_group("Name") in a BaseClass, then inheriting from that BaseClass in another class and there also using @export_group("Name"), with the same group name, then running the project and re-saving the inherited class the project crashes with 
```
ERROR: FATAL: Index p_index = 3 is out of bounds (size() = 3).
   at: get (./core/templates/cowdata.h:155)
```

sometimes the editor crashes too after a while.

### Steps to reproduce

1. open reproduction project
2. Run the project.
3. Open the "super"script
4. Press CTRL + S to save it.

### Minimal reproduction project

[MRP_.zip](https://github.com/godotengine/godot/files/12137412/MRP_.zip)

}
				}
#endif 
			} else {
				GDScriptInstance *gi = static_cast<GDScriptInstance *>(si);
				gi->reload_members();
			}
			E = N;
		}
	}
#endif 
	has_static_data = p_class->has_static_data;
	for (int i = 0; i < p_class->members.size(); i++) {
		if (p_class->members[i].type != GDScriptParser::ClassNode::Member::CLASS) {
			continue;
		}
		const GDScriptParser::ClassNode *inner_class = p_class->members[i].m_class;
		StringName name = inner_class->identifier->name;
		GDScript *subclass = p_script->subclasses[name].ptr();
		Error err = _compile_class(subclass, inner_class, p_keep_state);
		if (err) {
			return err;
		}
		has_static_data = has_static_data || inner_class->has_static_data;
	}
	p_script->_init_rpc_methods_properties();
	p_script->valid = true;
	return OK;
}
void GDScriptCompiler::convert_to_initializer_type(Variant &p_variant, const GDScriptParser::VariableNode *p_node) {