Add support for object updates to the journal publisher.

Related: swh-storage!139 (closed)

Note that it changes the value of temporary_prefix.

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Migrated from D916 (view on Phabricator)

Build is green See https://jenkins.softwareheritage.org/job/DJNL/job/tox/26/ for more details.

This diff shouldn't be needed if swh-storage!139 (closed) just pushes the changed objects to the existing temporary topics.

Merge request was abandoned

closed

mentioned in merge request swh-storage!139 (closed)

mentioned in merge request swh-docker-dev!36 (closed)