Fix test_forked_cw (#19680)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/19680
This was broken for quite some time because of an operator schema
check that went into effect at some point in time.
Reviewed By: manojkris
Differential Revision: D15055082
fbshipit-source-id: 7f730f9b810bdaffd69bab7ac4d02c5b2e40645b
