[GHF][BE] Add `__repr__` to `FlakyRule` (#101234)
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### <samp>🤖 Generated by Copilot at 9d9f7a4</samp>
> _`FlakyRule` class_
> _Defines rules for flaky tests_
> _Autumn leaves falling_
Pull Request resolved: https://github.com/pytorch/pytorch/pull/101234
Approved by: https://github.com/kit1980
