Apply rename of object_metadata to raw_extrinsic_metadata.

Changed in swh-storage > v0.11.3

Should fix the current build failure [1]

• [1] https://jenkins.softwareheritage.org/job/DLDBASE/job/tests/992/console

Test Plan

Will fail until we get a new release of swh-storage

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Migrated from D3624 (view on Phabricator)