Add fixture data with authKey fields

[dazza-codes]

The current fixture data (one_record.mrc) may not have the fields that could exercise the authority lookups in the unit tests. Let's add a fixture with these fields.

• add new fixture data
  • PR in Add fixture with authority fields to enable tests on authority URI lookups #32 fixes this
• enhance unit tests for the authority lookups
  • moved to Enhance unit tests for authority lookups #34