requirements: Add missing dependency

This is required and currently fails the debian build [1]

• [1] https://jenkins.softwareheritage.org/view/swh-debian%20(draft)/job/debian/job/packages/job/DSCRUB/job/gbp-buildpackage/4/console

Related to swh/infra/sysadm-environment#4228 (closed)

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Migrated from D7902 (view on Phabricator)