Port GitHub lister to swh.storage instead of sqlalchemy

GitHub lister should create entities and origins in the main swh db instead of relying on a separate database.

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Migrated from T164 (view on Phabricator)

marked this issue as related to swh-storage#163 (closed)

added GitHub lister priority:Normal labels

assigned to @olasd

closed

As of rDLSGH533f6fa1, the GitHub lister uses swh.storage instead of SQLAlchemy.