[llvm] [mlir] [MLIR][Shape] Preserve ub.poison during canonicalization (PR #179896)

[Akimasa Watanuki via llvm-commits]

Men-cotton wrote:

Hi @SakshamSinghal20  ,

Thank you so much for taking the time to work on this!
Unfortunately, this crash has actually already been fixed by another contributor in PR https://github.com/llvm/llvm-project/pull/183931.

We truly appreciate your effort, and we would be very happy to see more contributions from you in the future!

https://github.com/llvm/llvm-project/pull/179896