### 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)

const StringName &name = p_local->name;
	GDScriptParser::DataType base = parser->current_class->get_datatype();
	GDScriptParser::ClassNode *base_class = base.class_type;
	{
		List<MethodInfo> gdscript_funcs;
		GDScriptLanguage::get_singleton()->get_public_functions(&gdscript_funcs);
		for (MethodInfo &info : gdscript_funcs) {
			if (info.name == name) {
				parser->push_warning(p_local, GDScriptWarning::SHADOWED_GLOBAL_IDENTIFIER, p_context, name, "built-in function");
				return;
			}
		}
		if (Variant::has_utility_function(name)) {
			parser->push_warning(p_local, GDScriptWarning::SHADOWED_GLOBAL_IDENTIFIER, p_context, name, "built-in function");
			return;
		} else if (ClassDB::class_exists(name)) {
			parser->push_warning(p_local, GDScriptWarning::SHADOWED_GLOBAL_IDENTIFIER, p_context, name, "global class");
			return;
		} else if (GDScriptParser::get_builtin_type(name) != Variant::VARIANT_MAX) {
			parser->push_warning(p_local, GDScriptWarning::SHADOWED_GLOBAL_IDENTIFIER, p_context, name, "built-in type");
			return;
		}
	}
	while (base_class != nullptr) {