Fix flakiness in test_directory_add_get_arbitrary
By ignoring other attributes when raw_manifest is not None; just like we already do in test_revision_add_get_arbitrary and test_release_add_get_arbitrary.
Migrated from D8192 (view on Phabricator)
By ignoring other attributes when raw_manifest is not None; just like we already do in test_revision_add_get_arbitrary and test_release_add_get_arbitrary.
Migrated from D8192 (view on Phabricator)