Skip `test_minmax_illegal_dtype` on XLA (#39693)
Summary:
It's better to have skipping logic explicitly defined in test decorators rather than in some hard-to-find blacklists
Pull Request resolved: https://github.com/pytorch/pytorch/pull/39693
Differential Revision: D21947893
Pulled By: malfet
fbshipit-source-id: 3d0855eda7e10746ead80fccf84a8db8bf5a3ef1
