Update windows_arm64.yml

Author: martin-frbg

.github/workflows/windows_arm64.yml

@@ -29,6 +29,7 @@ jobs:
           Invoke-WebRequest https://github.com/llvm/llvm-project/releases/download/llvmorg-20.1.8/LLVM-20.1.8-woa64.exe -UseBasicParsing -OutFile LLVM-woa64.exe
           Start-Process -FilePath ".\LLVM-woa64.exe" -ArgumentList "/S" -Wait
           echo "C:\Program Files\LLVM\bin" | Out-File -FilePath $env:GITHUB_PATH -Encoding utf8 -Append
+          dir "C:\Program Files\LLVM\include\flang"
 
       - name: Install CMake and Ninja for Win-ARM64
         shell: pwsh