add info about Export-WindowsCapabilitySource

[VLG17]

#308

PR Summary

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 677ff62:

✅ Validation status: passed

File	Status	Preview URL	Details
docset/winserver2019-ps/dism/DISM.md	✅Succeeded	View (WindowsServer2019-ps)

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

[JohanFreelancer9]

Copy review - @VLG17, kindly commit the suggested change. Many thanks.

[learn-build-service-prod]

Learn Build status updates of commit f0d6c0a:

✅ Validation status: passed

File	Status	Preview URL	Details
docset/winserver2019-ps/dism/DISM.md	✅Succeeded	View (WindowsServer2019-ps)

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

[get-itips]

The article for the cmdlet is only under the Windows Server 2022 content, does this apply for the 2019 content that you are editing?