`UserButton` sign-out redirect props removed

The UserButton component no longer accepts sign-out redirect override props. Configure sign-out redirects using one of these methods:

Global configuration:

<ClerkProvider afterSignOutUrl="/signed-out">

Per-button with SignOutButton:

<SignOutButton redirectUrl='/goodbye'>Sign Out</SignOutButton>

Programmatic:

clerk.signOut({ redirectUrl: '/signed-out' });