### Godot version

v4.0.rc1.official [8843d9ad3]

### System information

Lubuntu

### Issue description

You can't use + or += to mutate typed arrays.

It seems to be not correctly getting the type information from the second operand.

An erudite poster on the discord puts it differently:
> it's more like operator + doesn't retain Array typing
> the syntax for Array Concatenation via operators, but the idea gets across i think


The error you see is:
```Trying to assign an array of type "Array" to a variable of type "Array[int]".```


### Steps to reproduce

```
	var Alice: Array[int] = [1,2,3]
	var Bob: Array[int] = [4,5,6]
	Alice += Bob
```
This will crash with the above error message.

### Minimal reproduction project

[plus_syntax_broken_demo_project.zip](https://github.com/godotengine/godot/files/10694514/plus_syntax_broken_demo_project.zip)

GDScriptParser::DataType type = make_enum_type(p_enum_name, p_base, p_meta);
	if (p_meta) {
		type.builtin_type = Variant::NIL; 
		type.is_pseudo_type = true;
	}
	HashMap<StringName, int64_t> enum_values;
	CoreConstants::get_enum_values(type.native_type, &enum_values);
	for (const KeyValue<StringName, int64_t> &element : enum_values) {
		type.enum_values[element.key] = element.value;
	}
	return type;
}
static GDScriptParser::DataType make_builtin_meta_type(Variant::Type p_type) {