Make the type of values of JournalWriter generic, so it works with types not from swh-model.
The indexer-storage will use this.
Depends on !186 (closed)
Migrated from D4082 (view on Phabricator)
The indexer-storage will use this.
Depends on !186 (closed)
Migrated from D4082 (view on Phabricator)