Don't save invalid addresses

The code that this pull request replaces calls `save(validate: false)` for the sole purpose of persisting invalid addresses. In fact, there is even a comment that says exactly that. But having records saved in an invalid can cause problems (it is in our app) and should be avoided.

This pull request accomplishes the task of associating a user with an order and immediately persisting that association, but it does't save invalid addresses.

The replaced code originated in 62addaaba4efe6f1ada54825ec8358d63fdee864.

Thanks.