[clang] [clang-tools-extra] [llvm] `cp -r` replaces symlinks, update to `cp -R` (PR #201463)

[Aiden Grossman via llvm-commits]

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@@ -4,7 +4,7 @@
 //
 // RUN: rm -rf %t.dir
 // RUN: mkdir -p %t.dir
-// RUN: cp -r %S/Inputs/identifier-naming/symlink %t.dir/symlink
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boomanaiden154 wrote:

I think this is fine because the actual symlink we care about for test fidelity is explicitly created later, but we need to tread carefully around symlink tests.

https://github.com/llvm/llvm-project/pull/201463