[nn] Fold : no batch dim (#64909)
Summary:
Fixes https://github.com/pytorch/pytorch/issues/64907
Reference: https://github.com/pytorch/pytorch/issues/60585
Pull Request resolved: https://github.com/pytorch/pytorch/pull/64909
Reviewed By: cpuhrsch, heitorschueroff
Differential Revision: D30991087
Pulled By: jbschlosser
fbshipit-source-id: 91a37e0b1d51472935ff2308719dfaca931513f3