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

[Vitaly Buka via llvm-commits]

vitalybuka wrote:

> (I was told to use `skip-presubmit-approval` label for CLs that I don't want reviewed)

I don't know meaning of this label, I can find only https://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20240722/601293.html which seems irrelevant.

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