[llvm] [LLVM] Do not require shell for some tests (PR #94595)

[Paul T Robinson via llvm-commits]

pogo59 wrote:

Yeah I think `ln` qualifies as deserving a `REQUIRES: shell` ?

For the unicode thing, seems sketchy to expect it to work on Windows. I cut the file down to just the `echo` command and tried to run it on my box, and got junk out.

https://github.com/llvm/llvm-project/pull/94595