in order.finalize! method use close method for adjustmens

If in extension we use Adjustment state machine in this way
```
Spree::Adjustment.class_eval do
  state_machine do
    after_transition :to => :closed, :do => :method_sample
  end
end
```
method is not called when user complete order. Works only when administrator close adjustment in order management. This little fix makes it works in both ways. It makes update query for every adjustment, but in checkout page I thinks this is not big problem.