Fix destination.type value for Biz Acct Transfers endpoint

[alandn-circle]

The value being supplied for a POST to create a Biz Acct transfer in the Sample App is incorrect: https://sample-sandbox.circle.com/debug/businessAccount/transfers/create

Specifically, the app supplies a value of address which is not allowed by the destination endpoint:

{
  "idempotencyKey": "7ee50812-4edd-47fb-a78f-7b69c9bbf040",
  "amount": {
    "amount": "10",
    "currency": "USD"
  },
  "destination": {
    "type": "address",
    "addressId": "<SOME_RANDOM_ADDRESS_UUID>"
  }
}

We want to change destination.type to type verified_blockchain to reflect changes on the official Circle API reference, relative to business account transfers as seen here.

[kristinfritsch]

We also need to update the merchant dashboard. I can take care of it.