### 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)

if ((p_property.usage & PROPERTY_USAGE_CLASS_IS_ENUM) && p_property.class_name != StringName()) {
				if (CoreConstants::is_global_enum(p_property.class_name)) {
					result = make_global_enum_type(p_property.class_name, StringName(), false);
					result.is_constant = false;
				} else {
					Vector<String> names = String(p_property.class_name).split(ENUM_SEPARATOR);
					if (names.size() == 2) {
						result = make_native_enum_type(names[1], names[0], false);
						result.is_constant = false;
					}
				}
			}
			
		}
	}
	return result;
}
bool GDScriptAnalyzer::get_function_signature(GDScriptParser::Node *p_source, bool p_is_constructor, GDScriptParser::DataType p_base_type, const StringName &p_function, GDScriptParser::DataType &r_return_type, List<GDScriptParser::DataType> &r_par_types, int &r_default_arg_count, BitField<MethodFlags> &r_method_flags, StringName *r_native_class) {
	r_method_flags = METHOD_FLAGS_DEFAULT;
	r_default_arg_count = 0;
	if (r_native_class) {
		*r_native_class = StringName();
	}
	StringName function_name = p_function;
	bool was_enum = false;
	if (p_base_type.kind == GDScriptParser::DataType::ENUM) {
		was_enum = true;
		if (p_base_type.is_meta_type) {
			
			p_base_type.kind = GDScriptParser::DataType::BUILTIN;