remove tuple logic in constant propagation (#31840)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/31840
The next PR in this stack makes tuples insertable as constants, so we can remove special handling of tuples in constant propagation.
Test Plan: Imported from OSS
Differential Revision: D19439515
Pulled By: eellison
fbshipit-source-id: c58f153157f1d4eee4c1242decc4f36e41c1aa05
