updated the docs for BatchNorm1d and InstanceNorm1d (#71371)
Summary:
Fixes input shape notation inconsistencies mentioned here: https://github.com/pytorch/pytorch/issues/71366
Pull Request resolved: https://github.com/pytorch/pytorch/pull/71371
Reviewed By: anjali411
Differential Revision: D33746814
Pulled By: jbschlosser
fbshipit-source-id: 21a080ea30192cd109e437f758afe54d57778724
(cherry picked from commit c1fecebd036dab6ed1f6af58263e9fda5f8d435a)
