[iOS] Merchant/Payee filter duplicate contacts

Issue: Duplicate Merchants and Payees exist in the Merchant/Payee Search functionality, even when these payments/transactions are sent to exactly the same person.

Details to reproduce:

  1. Have a large diverse transaction history with multiple payments to different merchants and payees at different times
  2. Use the contact search functionality.

OS: iOS 12.1.3 (16D39)
Device: iPhone 8
App Version: 2.32.0