fix 'should import car with roots but no blocks' test

[SgtPooki]

see https://github.com/ipfs/js-kubo-rpc-client/pull/83#discussion_r1048539382

from @lidel

This is an important smoke-test we should not skip and fix sooner than later (i vaguely remember Filecoin genesis blocks were "special snowflakes" that forced IPLD team to course-correct some specs).

This test is re-enabled, but has part of it temporarily commented out. https://github.com/ipfs/js-kubo-rpc-client/blob/28190805dee25c70c1122cde41397d97deeba70d/test/interface-tests/src/dag/import.js#L158-L161

[TinyTb]

We should consider removing the pinning tests from the RPC client. Tests should validate that the daemon receives the correct params; Kubo should ensure that it does the right thing.