fixup panic

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

kgo.go

@@ -460,6 +460,7 @@ func NewBroker(opts ...broker.Option) *Broker {
 	}
 
 	return &Broker{
+		connected: &atomic.Uint32{},
 		opts:      options,
 		kopts:     kopts,
 	}