Warcraft 3 Reforged (PTR) updating despite me never owning Warcraft 3 Reforged

Title says it all, Warcraft 3 Reforged is updating, and taking space on my computer, and I don’t have any way to pause or cancel it. Is there any solution to this issue, or am I boned?

You must have Warcraft 3 classic PTR installed somewhere on your machine. The Battle.net app keeps that updated now.