[llvm] [libc++][ci] Use upload-artifact at v4 instead of @v3 (PR #79854)

[Tom Stellard via llvm-commits]

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@@ -75,7 +75,7 @@ jobs:
           CC: ${{ matrix.cc }}
           CXX: ${{ matrix.cxx }}
           ENABLE_CLANG_TIDY: ${{ matrix.clang_tidy }}
-      - uses: actions/upload-artifact at v3
+      - uses: actions/upload-artifact at v4
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tstellar wrote:

We've been advised to use the full git hash rather than tags when referencing these actions.  See https://github.com/llvm/llvm-project/commit/f3524e9aebbfabed0c60d0087b39ce14d8f778da

https://github.com/llvm/llvm-project/pull/79854