### 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)

}
						base = look_class->get_datatype();
						found = true;
						break;
					}
					if (look_class->has_member(name)) {
						resolve_class_member(look_class, name, id);
						GDScriptParser::ClassNode::Member member = look_class->get_member(name);
						GDScriptParser::DataType member_datatype = member.get_datatype();
						switch (member.type) {
							case GDScriptParser::ClassNode::Member::CLASS:
								break; 
							case GDScriptParser::ClassNode::Member::CONSTANT:
								if (member_datatype.kind != GDScriptParser::DataType::SCRIPT && member_datatype.kind != GDScriptParser::DataType::CLASS) {
									push_error(vformat(R"(Constant "%s" is not a preloaded script or class.)", name), id);
									return ERR_PARSE_ERROR;
								}
								break;
							default:
								push_error(vformat(R"(Cannot use %s "%s" in extends chain.)", member.get_type_name(), name), id);
								return ERR_PARSE_ERROR;
						}
						base = member_datatype;
						found = true;
						break;
					}
				}
				if (!found) {
					push_error(vformat(R"(Could not find base class "%s".)", name), id);
					return ERR_PARSE_ERROR;