[llvm] [llvm-objcopy] Fix prints wrong path when section output path doesn't exist (PR #125345)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,37 @@
+## Show that llvm-objcopy report that section file path is not exists.
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MaskRay wrote:

Place the test into the primary test `dump-section.test`. We often use one test file for both positive and negative tests. Sometimes this actually improves test discoverability

https://github.com/llvm/llvm-project/pull/125345