### Godot version

4.0.beta10

### System information

Windows 11

### Issue description
UPDATE: This problem only occurs when the source code contains inner classes

Before 4.0.Beta9, I could get a GDScript instance by `GDScript.new()` and then set the `source_code` property and then `reload()`, but now it throws an error 
```
USER SCRIPT ERROR: Parse Error: Could not find script "".
   at: GDScript::reload (built-in:1644)
```
In my software, I use the above method when the user modifies the code text, and then read the godot log to implement real-time error checking of the custom user script editor. But now this functionality is completely broken

### Steps to reproduce

1. Create a GDScript instance by `GDScript.new()`
2. set the `source_code` property and then `reload()`

### Minimal reproduction project

N/A
Ref<GDScript> sqscr = p_resource;
	ERR_FAIL_COND_V(sqscr.is_null(), ERR_INVALID_PARAMETER);
	String source = sqscr->get_source_code();
	{
		Error err;
		Ref<FileAccess> file = FileAccess::open(p_path, FileAccess::WRITE, &err);
		ERR_FAIL_COND_V_MSG(err, err, "Cannot save GDScript file '" + p_path + "'.");
		file->store_string(source);
		if (file->get_error() != OK && file->get_error() != ERR_FILE_EOF) {
			return ERR_CANT_CREATE;
		}
	}
	if (ScriptServer::is_reload_scripts_on_save_enabled()) {
		GDScriptLanguage::get_singleton()->reload_tool_script(p_resource, true);
	}
	return OK;
}
void ResourceFormatSaverGDScript::get_recognized_extensions(const Ref<Resource> &p_resource, List<String> *p_extensions) const {
	if (Object::cast_to<GDScript>(*p_resource)) {
		p_extensions->push_back("gd");
	}
}
bool ResourceFormatSaverGDScript::recognize(const Ref<Resource> &p_resource) const {
	return Object::cast_to<GDScript>(*p_resource) != nullptr;
}