Make sure api server uses explicit configurations

All workers use the explicit configuration scheme.

Make sure every server does as well:

• vault
• swh/infra/puppet/puppet-swh-site!170 (closed): deposit
• swh/devel/swh-storage!902 (closed): storage
• swh/devel/swh-objstorage!129 (closed): objstorage
• swh/devel/swh-indexer!441 (closed): indexer-storage
• rDSCHce90908cd0c32ce978ae813aa73235850cdeb4d2: scheduler
• swh/devel/swh-web!992 (closed): webapp

Related swh/devel/swh-core#1410

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Migrated from T1533 (view on Phabricator)