Correct dashes to hyphens

[minhtaile2712]

Using dashes can be problematic, especially when copying into PowerShell, as PowerShell will truncate them, making the command incorrect. Use hyphens instead.

[learn-build-service-prod]

Learn Build status updates of commit f0d9041:

✅ Validation status: passed

File	Status	Preview URL	Details
virtualization/hyper-v-on-windows/user-guide/enable-nested-virtualization.md	✅Succeeded

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