Kill discover_sparse_tensor_operations. (#25589)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/25589
It's not used anymore.
Test Plan: Imported from OSS
Differential Revision: D17172501
Pulled By: gchanan
fbshipit-source-id: 4fff9e48358015bcf886294b8db359c3cc7acafa
