[llvm] [lit] Fix lit hang on pool join when exception is thrown (PR #131881)

[David Garcia Orozco via llvm-commits]

ayylol wrote:

Hey @DavidSpickett, I should clarify. I was able to reproduce the lit hang that I reported in #133914  (which this PR fixes) with python 3.12.3. As for the cpython issue, I added it to the description because it was cited as the likely root cause for the stack overflow thread I've linked. However, looking at it I think you are right that issue isn't reproducible in python versions that are used for LLVM, so i think its unlikely the root cause for this case.

Going to remove it from the description.

https://github.com/llvm/llvm-project/pull/131881