[Backup] Restore services not implemented in backup script.

As part of upcoming CND release we are going to support restore flags like --disable-analytics, --disable-eventing, -disable-gsi etc. 

These services have been added as a part of CouchbaseBackupRestoreSpec: https://github.com/couchbase/couchbase-operator/blob/7576a23fedc8046201abd8037adc5ab18a5541a1/pkg/apis/couchbase/v2/types.go#L399 

But the same has not been added to the backup script.

https://github.com/couchbaselabs/couchbase-operator-backup/blob/master/backup.py#L180

On a separate note, these flags won't be registered with cbbackupmgr when appended with --services flag, we need them as individual entities.

This is causing the tests to restore the disabled service components.