[clang-tools-extra] [clang-tools-extra] Remove 'REQUIRES: shell' from lit tests. (PR #156950)

[Baranov Victor via cfe-commits]

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@@ -1,4 +1,4 @@
-// REQUIRES: shell
+// UNSUPPORTED: system-windows
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vbvictor wrote:

Will the test not run on Windows anymore?
This script is pretty important for users, so I don't think it's a good idea to remove it from windows test-suite

https://github.com/llvm/llvm-project/pull/156950