Prepare fixture data for account sync tests (#493)

* Rename account balance field for clarity

`original_balance` and `original_currency` may infer that these values are "original" to the account.  In reality, they represent the "current" balance and currency on the account.

* Prepare fixture data for account sync testing

* Update to new field

* Fix conflicts

* Remove local schema change

test/models/valuation_test.rb

@@ -1,7 +1,4 @@
 require "test_helper"
 
 class ValuationTest < ActiveSupport::TestCase
-  # test "the truth" do
-  #   assert true
-  # end
 end