Move get_swh_persistent_ids function in common.identifers module
That function was missed when moving identifiers related ones in 8b3e0ce5.
Migrated from D3105 (view on Phabricator)
Staging instance, all changes can be removed at any time
That function was missed when moving identifiers related ones in 8b3e0ce5.
Migrated from D3105 (view on Phabricator)