code: Delta newDeleteStorage(Storage storage) {
          return Deltas.mapBuilder()
                  .update(STORAGE.key(), Deltas.mapBuilder()
                          .remove(storage.getUuidString())
                          .deleteIfEmpty()
                          .build())
                  .deleteIfEmpty()
                  .build();
      }
docs: Final delete of table and/or storage metadata after all data has been purged for the last time.