Fix chronik client websocket integration test

Summary: This was missing a few updates for preconsensus.

Test Plan:

./contrib/teamcity/build-configurations.py chronik-client-integration-tests

Reviewers: #bitcoin_abc, bytesofman

Reviewed By: #bitcoin_abc, bytesofman

Subscribers: bytesofman

Differential Revision: https://reviews.bitcoinabc.org/D18832