Update Set-SPMachineKey.md

[Rick-Anderson]

Part of SFI effort

[learn-build-service-prod]

Learn Build status updates of commit 1723c6d:

✅ Validation status: passed

File	Status	Preview URL	Details
sharepoint/sharepoint-server-ps/sharepoint-server/Set-SPMachineKey.md	✅Succeeded	View (sharepoint-server-ps)

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