You can create a backup of your Production database and restore it in the test environment. You can easily do this from the Cloud Portal
The method differs a bit between the V3 cloud vs the V4 cloud. In V3 it is real easy and you can select to restore a backup to a different environment. In the V4 cloud you need to download the backup from production firtst and then do an upload to the test environment. Note that this action clears the test environment. So the V3 cloud the proces is much easier and I hope this in the near future will also be possible in the V4 cloud.