Fix a `-Wdefaulted-function-deleted`
Fix a `-Wdefaulted-function-deleted`

Summary: Fix an issue warned by newer Clang.

Reviewed By: yuxuanchen1997

Differential Revision: D26107837

fbshipit-source-id: 3ee66f1cae7dd1588c9226eccfb95702adb9c785

facebook/redex,facebook/redex,facebook/redex,facebook/redex,facebook/redex,facebook/redex,facebook/redex,facebook/redex,facebook/redex