Replace assertRaisesRegex w/ assertRaisesRegexWithHighlight test_backends.py (#55493)
Summary:
Step to resolving https://github.com/pytorch/pytorch/issues/55072
Pull Request resolved: https://github.com/pytorch/pytorch/pull/55493
Reviewed By: gmagogsfm
Differential Revision: D27626192
Pulled By: janeyx99
fbshipit-source-id: 047b7b6754e21388f52489160d712858b7aa0288
