The issue is that in older fcvs, we set the primaryShardIds to none: https://github.com/10gen/mongo/blob/8db8ac86ddc617c0f434cfdce553094fff667644/src/mongo/db/s/resharding/resharding_donor_recipient_common.cpp#L341.

However, the tassert check is using a feature flag that is enable_on_transitional_fcv_UNSAFE so the logic can get triggered during upgrading. Although the resharding will eventually be aborted even without the tassert, tasserts in tests are considered fatal so it will be flagged as a failure.

The issue is that we only set version context when FCV is 9.0. However, unset version context does not mean v8.0, but whatever the latest value of fcv is