[Cashtab] [Cashtab] [final bch-api deprecation p5] Stop trying to reconnect to bad websockets

Summary:
T2730, T2735

Depends on D12791

When chronik changes to a new URL, close the old websocket and stop trying to reconnect to it.

Test Plan:
npm start
Wait for API error
Wait for app to self correct to the right API
Note that the app stops trying to reconnect to the old websockets

Reviewers: #bitcoin_abc, emack

Reviewed By: #bitcoin_abc, emack

Differential Revision: https://reviews.bitcoinabc.org/D12792