Summary:
Oculus wants to preserve the "do not show binary diff" config while running
`hg export` in automation, since printing the binary diff might just OOM the
container. Let's add a plain exception for it.
Reviewed By: zhh95
Differential Revision: D13111212
fbshipit-source-id: 34af58ac0917de3b3231e637774896d882585e26
