### Godot version

v4.0.beta17.official [c40020513]

### System information

Apple M1 Max - macOS Ventura 13.1 (22C65)

### Issue description

I am getting an error due to functions no longer returning the correct typed array, when the function concatenates arrays and returns it.

In other words, the following fails:

```
func add_arrays() -> Array[ClassA]:
	var array_1: Array[ClassA] = []
	var array_2: Array[ClassA] = []
	return array_1 + array_2
```

<img width="864" alt="Screenshot 2023-02-02 at 1 02 53 PM" src="https://user-images.githubusercontent.com/905216/216320503-475bf4a1-353e-455c-87d5-69d036db706c.png">

I'm assuming when concatenating, the typing changes to a generic `Array` now? Just a guess. 

### Steps to reproduce

N/A

### Minimal reproduction project

[Godot Crash Project.zip](https://github.com/godotengine/godot/files/10568780/Godot.Crash.Project.zip)

if (info.path.get_extension().to_lower() != GDScriptLanguage::get_singleton()->get_extension()) {
					push_error(vformat(R"(Singleton %s is not a GDScript.)", info.name), id);
					return ERR_PARSE_ERROR;
				}
				Ref<GDScriptParserRef> info_parser = get_parser_for(info.path);
				if (info_parser.is_null()) {
					push_error(vformat(R"(Could not parse singleton from "%s".)", info.path), id);
					return ERR_PARSE_ERROR;
				}
				Error err = info_parser->raise_status(GDScriptParserRef::INHERITANCE_SOLVED);
				if (err != OK) {
					push_error(vformat(R"(Could not resolve super class inheritance from "%s".)", name), id);
					return err;
				}
				base = info_parser->get_parser()->head->get_datatype();
			} else if (class_exists(name)) {
				base.kind = GDScriptParser::DataType::NATIVE;
				base.native_type = name;
			} else {
				
				bool found = false;
				List<GDScriptParser::ClassNode *> script_classes;
				get_class_node_current_scope_classes(p_class, &script_classes);
				for (GDScriptParser::ClassNode *look_class : script_classes) {
					if (look_class->identifier && look_class->identifier->name == name) {
						if (!look_class->get_datatype().is_set()) {
							Error err = resolve_class_inheritance(look_class, id);
							if (err) {
								return err;
							}