* support mnist and resnet dygraph_to_static test

* make FLAGS_use_mkldnn a public flag

* fix test_get_set_flags

* Change name of a function

* Rerun CIs commit

* Fix oneDNN dygraph training
Co-authored-by: NAdam <38704900+grygielski@users.noreply.github.com>
Co-authored-by: Ngrygielski <adam.grygielski@gmail.com>