Handle case where document has been deleted in OZ

[SilviaAmAm]

If OAB deletes the ZIO, it stores a reference to the EIO to delete in the ResultStore object.

If in the mean time the EIO is deleted in OZ, when OAB tries to delete it, it gets an error response from OZ (see sentry maykin-media/issues/388797).

If we get a 404 from OZ, we should not raise an error, since the document does not exist anymore anyway. We should however log that it was not deleted by OAB.