Auto merge of #22387 - o0Ignition0o:mach_run_nightly_macos, r=jdm

./mach run -n on mac os.

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Add macos support to the -n flag.

Followup to #20122 , this PR will add macos support to the -n flag.
 This is part of step two for #19505

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- [ ] These changes fix #__ (github issue number if applicable).

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