Fixes #12087 - Update descriptions of comment-based help keywords

[sdwheeler]

PR Summary

Update descriptions of comment-based help keywords

• Fixes AB#434188
• Fixes Update description of .INPUTS and .OUTPUTS keywords to state they can be repeated #12087

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 a54f6e5:

✅ Validation status: passed

File	Status	Preview URL	Details
reference/5.1/Microsoft.PowerShell.Core/About/about_Comment_Based_Help.md	✅Succeeded	View (powershell-5.1)
reference/7.4/Microsoft.PowerShell.Core/About/about_Comment_Based_Help.md	✅Succeeded	View (powershell-7.4)
reference/7.5/Microsoft.PowerShell.Core/About/about_Comment_Based_Help.md	✅Succeeded	View (powershell-7.5)
reference/7.6/Microsoft.PowerShell.Core/About/about_Comment_Based_Help.md	✅Succeeded	View (powershell-7.6)
reference/docs-conceptual/developer/help/comment-based-help-keywords.md	✅Succeeded	View (>=powershell-5.1)

For more details, please refer to the build report.

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