[Cashtab] Add unit tests for parseAddressForParams

Summary: As per feedback from D14116, this diff adds unit tests to the existing parseAddressForParams function before moving it out of Ticker.js in D14116.

Test Plan: npm test

Reviewers: bytesofman, Fabien, #bitcoin_abc

Reviewed By: Fabien, #bitcoin_abc

Differential Revision: https://reviews.bitcoinabc.org/D14117