Port packagist lister to the new Lister API

The packagist lister implementation must be ported to the new swh.lister.pattern.Lister API.

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Migrated from T2991 (view on Phabricator)

mentioned in merge request !204 (closed)

marked this issue as related to swh-scheduler#2442 (closed)

added Lister priority:Normal labels

assigned to @anlambert

added state:wip label

mentioned in commit ff05191b

removed state:wip label

closed