Ingest crates.io (Rust)

• swh/devel/swh-lister#1424, swh/devel/swh-lister!270 (closed): Implement lister
• swh/devel/swh-loader-core!424 (closed): Implement loader
• #4104: Run in docker
• swh/devel/swh-docs!298 (closed): Document lister
• Document loader
• Deploy on staging
• Call for public review
• Deploy on production

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Migrated from T4104 (view on Phabricator)