ephemeralVolume should have a default false value

When trying to apply the backup yaml from the documentation, the following error is thrown:

error: error validating "backup-example.yaml": error validating data: ValidationError(CouchbaseBackup.spec): missing required field "ephemeralVolume" in com.couchbase.v2.CouchbaseBackup.spec; if you choose to ignore these errors, turn validation off with --validate=false 

Steps to reproduce:

For a Couchbase cluster with a backup set in its spec:

kubectl -f apply backup.yaml

backup.yaml:
apiVersion: couchbase.com/v2
kind: CouchbaseBackup
metadata:
name: my-backup
spec:
strategy: full_incremental
full:
schedule: "0 3 * * 0"
incremental:
schedule: "0 3 * * 1-6"
size: 20Gi