Clone an existing Cloud SQL instance and optionally acquire it into the deployment.

• Cloud SQL tends to return 403 when something can't be found, so if you see an error like:

  "ResourceErrorCode": 403, "message": "The client is not authorized to make
  this request.", "requestPath": "https://...
  

  Then ensure that the Instance in the requestPath actually exists and that the authority that Deployment Manager uses has permissions on it.

• If the new Instance's name is already taken, then you will receive an error like:

  "ResourceErrorCode": "409", "message": "The Cloud SQL instance already
  exists."
  

  Note that Cloud SQL Instance names are reserved for a week after instance deletion, see https://cloud.google.com/sql/docs/mysql/delete-instance.