add xla tests to enabled-configs (#16761)
Summary:
This should enable xla tests thus let master xla tests pass.
As usual, I will add the branch filters back before landing.
Thanks ezyang !
Pull Request resolved: https://github.com/pytorch/pytorch/pull/16761
Differential Revision: D13959746
Pulled By: ailzhang
fbshipit-source-id: 7384da281d093d16edccb4283c74e47ac659eeff
