[llvm] [SPIR-V][NFC] Require asserts on 2 tests (PR #75087)

[Natalie Chouinard via llvm-commits]

sudonatalie wrote:

Since we merged #74849 , the SPIR-V Tests buildbot should pass now with or without this change, but adding this quick follow-up to make the test requirements more explicit anyways.

https://github.com/llvm/llvm-project/pull/75087