(GH-10798) Clarify how to find exception names in about_Trap

[michaeltlombardi]

PR Summary

Prior to this change, the about_Trap topic explained how to use specific exceptions with a trap statement, but not how to discover the exception names for that purpose.

This change:

• Adds prose and example to the section "Trapping specific errors" that covers how to get the full name of an exception
• Resolves Specific Error Exception Fullname #10798
• Fixes AB#200723

Note

The first commit in this change set addresses syntax, grammar, and formatting issues with the article and is unrelated to the issue the PR addresses except as a maintenance item.

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 f2efd9e:

✅ Validation status: passed

File	Status	Preview URL	Details
reference/5.1/Microsoft.PowerShell.Core/About/about_Trap.md	✅Succeeded	View (powershell-5.1)
reference/7.2/Microsoft.PowerShell.Core/About/about_Trap.md	✅Succeeded	View (powershell-7.2)
reference/7.3/Microsoft.PowerShell.Core/About/about_Trap.md	✅Succeeded	View (powershell-7.3)
reference/7.4/Microsoft.PowerShell.Core/About/about_Trap.md	✅Succeeded	View (powershell-7.4)

For more details, please refer to the build report.

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