Fixes #11255 - Add link to RestorePointType docs

[sdwheeler]

PR Summary

Add link to RestorePointType docs

• Fixes Explain the different types of restore point #11255
• Fixes AB#284328

PR Checklist

• Descriptive Title: This PR's title is a synopsis of the changes it proposes.
• Summary: This PR's summary describes the scope and intent of the change.
• Contributor's Guide: I have read the contributors guide.
• Style: This PR adheres to the style guide.

[learn-build-service-prod]

Learn Build status updates of commit 5a2bb10:

⚠️ Validation status: warnings

File	Status	Preview URL	Details
reference/5.1/Microsoft.PowerShell.Management/Checkpoint-Computer.md	⚠️Warning	View (powershell-5.1)	Details

reference/5.1/Microsoft.PowerShell.Management/Checkpoint-Computer.md

• Line 0, Column 0: [Warning: file-not-found - See documentation] Invalid file link: 'windows/win32/sr/restore-point-description-text'.

For more details, please refer to the build report.

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[learn-build-service-prod]

Learn Build status updates of commit e997f66:

✅ Validation status: passed

File	Status	Preview URL	Details
reference/5.1/Microsoft.PowerShell.Management/Checkpoint-Computer.md	✅Succeeded	View (powershell-5.1)

For more details, please refer to the build report.

For any questions, please:

• Try searching the learn.microsoft.com contributor guides
• Post your question in the Learn support channel