To clone a DBCluster custom resource with name "postgresql-src-db" to a new DBCluster custom resource "postgresql-dst-db", run:
gdcloud database clusters clone postgresql-src-db postgresql-dst-db \
--point-in-time=2006-01-02T15:04:05Z
必須フラグ
--point-in-time string defines a past state of the DBCluster to clone (should be RFC 3339 format).