Copy/paste error in sample code

In `server/routes/pilots/stripe.js` there is a sample:

```javascript
// 'stripe_user[street_address]': req.user.address || undefined,
// 'stripe_user[city]': req.user.city || undefined,
// 'stripe_user[zip]': req.user.postalCode || undefined,
// 'stripe_user[state]': req.user.city || undefined,
```

The last line (49) copies "city" into "state". It should copy "state", not "city".