protofsm: don't return error on broadcast fail

We don't return an error on broadcast fail as the broadcast might have
failed due to insufficient fees, or inability to be replaced, which may
happen when one side attempts to unnecessarily bump their coop close
fee.

protofsm/state_machine.go

@@ -436,7 +436,7 @@ func (s *StateMachine[Event, Env]) executeDaemonEvent(ctx context.Context,
 			daemonEvent.Tx, daemonEvent.Label,
 		)
 		if err != nil {
-			return fmt.Errorf("unable to broadcast txn: %w", err)
+			log.Errorf("unable to broadcast txn: %v", err)
 		}
 
 		return nil