02 / 03 Missing Credentials

While this tutorial is pretty old, it's still in use today:
https://docs.couchbase.com/server/current/backup-restore/cbbackupmgr-tutorial.html

Recommended updates:
- 01 Loads the beer-sample and travel-sample, but does not create any indexes referred by the tutorial (views are included for beer-sample).
- 02/03 curl requests should likely include the missing credentials for any recent version of couchbase.
- 03 reports `updated two documents and created two documents` but it only GETs four documents.