Fix batchnorm backward bug (#5602)

* add argmax test

* fix ci error

* fix docstring warning

* fix tensor greater and less bug

* fix conflict

* add test_flow_xxx_against_pytorch func

* fix bn autograd bug

* fix bn autograd bug

Co-authored-by: oneflow-ci-bot <69100618+oneflow-ci-bot@users.noreply.github.com>