[bug] Combo crashes with empty string item

[aj3423]

What happend?

Combobox crashes if the items contain empty string like: items = []string{"111", "", "333"}

Code example

main.go

```golang package main import "github.com/AllenDang/giu" var sel int32 func loop() { giu.SingleWindow().Layout( giu.Combo("", "", []string{ "111", "", // <------ crash "333", }, &sel), ) } func main() { wnd := giu.NewMasterWindow("", 400, 200, 0) wnd.Run(loop) } ```

To Reproduce

1. Run my demo
2. will see the crash...

Version

(latest)

OS

Fedora 40