Enable Constant Folding Tests (#38751)
Summary:
Enable tests for constant folding since constant folding is enabled for opset 12
Pull Request resolved: https://github.com/pytorch/pytorch/pull/38751
Differential Revision: D21728013
Pulled By: ezyang
fbshipit-source-id: e0ed9ad62d8b781eacfdf894e8c9609fe7e778bd
