[clang] [Driver] Add ExclusiveGroup feature to multilib.yaml. (PR #69447)

[Fangrui Song via cfe-commits]

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@@ -0,0 +1,70 @@
+# REQUIRES: shell
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MaskRay wrote:

If `LIT_USE_INTERNAL_SHELL=1 llvm-lit ..` passes, you can remove `# REQUIRES: shell` (dependency on an external shell)

https://github.com/llvm/llvm-project/pull/69447