Add logic to detect "new" rank cubes

[SanderDevisscher]

One thing, already mentioned in the comment: how to check that there are no other "new" ranks (= cubes)? I think somewhere an action should fail if this occurs. Quite sure not the action about the cube metadata.Maybe the action taking the taxa of the backbone linked to the unified checklist?

Originally posted by @damianooldoni in #333 (review)

We can certainly include some logic to detect "new" rank cubes. I'll include this step when I retrieve the GRIIS checklist from gbif (see get_griis_checklist.yaml).

Originally posted by @SanderDevisscher in #333 (comment)