Remove --cross from osx-arm64 on native host

[am11]

#122420

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[am11]

@agocke, mystery solved. I included cmake log file (CMakeConfigureLog.yaml) in log artifacts, it showed the error:

...
      stderr: |
        Unknown system error -86
      exitCode: "FAILED_TO_RUN"

We were expecting it to run on osx-arm64, right? I printed uname -a and it says x86_64:

>>>>>>>[UNAME]>>>>> Darwin Mac-1765425169811.local 24.6.0 Darwin Kernel Version 24.6.0: Wed Oct 15 21:12:21 PDT 2025; root:xnu-11417.140.69.703.14~1/RELEASE_X86_64 x86_64

DevOps is offering a privew of macOS arm64 (https://devblogs.microsoft.com/devops/upcoming-updates-for-azure-pipelines-agents-images/#mac-os), can we get it enabled for runtime repo or is it too early? 👀

[agocke]

We were expecting it to run on osx-arm64, right?

Nope. That's what I meant when I said we're only updating the helix runners, not the build machines. The build machines are all x64. We can't access any of the arm64 previews in our private pools yet.