UI support for MU03 on test nets

[philbow61]

Description For MU03 the UI needs to be updated to support new exchanges. Namely, USDC/cBRL, USDC/cEUR and EUROC/cEUR

Acceptance Criteria

• [x] UI allows users to swap via the new exchanges on Baklava
• [x] UI allows users to swap via the new exchanges on Alfajores

[denviljclarke]

I created a separate issue for the main net version of these changes here #100