Revert D27246997: [pytorch][PR] Fix reference cycle in sparse coalesce graph
Test Plan: revert-hammer
Differential Revision:
D27246997 (https://github.com/pytorch/pytorch/commit/815bfad28c8dc7fd3bd89c5e5a821679f73702fc)
Original commit changeset: 0fe6c1104350
fbshipit-source-id: 4d345718589a642d3c65474b266342285205ccdf
