sonner 1.5 version issue. Multiple stack toast closing at same time.

[amateur-hacker]

I'm experiencing an issue in version 1.5 of Sonner where multiple toasts close at the same time. In previous versions, this worked correctly. Specifically, when opening multiple toasts, such as three toasts, they all close together when the last toast's timer finishes.

[emilkowalski]

Fixed in #501