[llvm] [mlir][spv] Enable spirv-tests CI to run for mlir-spv target tests (PR #152124)

[Davide Grohmann via llvm-commits]

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@@ -9,6 +9,7 @@ on:
     paths:
       - 'llvm/lib/Target/SPIRV/**'
       - 'llvm/test/CodeGen/SPIRV/**'
+      - 'mlir/test/Target/SPIRV/**'
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davidegrohmann wrote:

Why? They do not generate SPIR-V assembly, so they do not require spirv-tools support. Or am I missing something?

https://github.com/llvm/llvm-project/pull/152124