Log Message:
finance/ruby-activemerchant: update to 1.121.0

1.121 (2021-06-08)

* Braintree: Lift restriction on gem version to allow for backwards
  compatibility [naashton] #3993
* Payment Express/Windcave: Send amount on verify calls [cdmackeyfree] #3995
* Orbital: Use billing_address name as fallback [curiousepic] #3966
* vPOS: handle shop_process_id correctly [therufs] #3996
* Checkout v2: Support metadata field [saschakala] #3992
* Adyen: Support networkTxReference field [naashton] #3997
* Paypal Express: Enable PayPal express reference transaction request to
  send merchant session id [janees-e] #3994