[llvm] [Github] Make Windows container use zstd (PR #167022)

[Baranov Victor via llvm-commits]

https://github.com/vbvictor commented:

LG as long as it works, but I don't have a strong opinion on this change.

One drawback I see is the increasing pool of tools we use. This can bring us more potential bugs that could appear during version bumps. Also, entry barrier is slightly increased with introduction of `scopeo`. 
However, if the decompress speed is favorable over potential complexity/bugs I have nothing against.

https://github.com/llvm/llvm-project/pull/167022