docker/conf/mirror/replayer: Use a more robust configuration
requested to merge anlambert/swh-environment:docker-mirror-robustify-replayer-storage-conf into master
As there is multiple replayer services, with previous configuration, we could be hit by concurrency issues related to database transactions inserting revisions with the same author in parallel:
ERROR: duplicate key value violates unique constraint "person_fullname_idx"
So use a more robust storage configuration (same as loader service) to mitigate those issues.