CLC-4245: make smarter use of test UIDs

Currently the user-driven finances test iterates through all the accounts in a CSV file.  With this pull request, the test instead iterates only through accounts in a JSON file if they have a property "finances" with value true.  This will allow new user-driven UI tests to draw from the same data file without using all the same UIDs.

If this PR is merged, then I'll replace the CSV file on the Bamboo server.