[compiler-rt] [NFC] Fix flakiness in test if run unsharded (PR #112439)

[Vitaly Buka via llvm-commits]

vitalybuka wrote:

Ok, it's documented, but it has a different name https://llvm.org/docs/CodeReview.html#code-review-workflow

https://github.com/llvm/llvm-project/pull/112439