Ray SGD v1 has been denoted as a deprecated API for a while. This PR fully deprecates Ray SGD v1. An error will be raised if ray.util.sgd package is attempted to be imported.
Closes#16435
Horovod updated the attributes of DistributedTrainableCreator and args to create Horovod RayExecutor.
horovod/horovod@a729ba7
The major issue is Horovod deprecated "slot" concept, use "worker" instead, which is more consistent with Generic Ray worker. The issue is currently blocking Uber DL trainers to use raytune.
This commit updates the Horovod RayExecutor init args.
Co-authored-by: Kai Fricke <kai@anyscale.com>
