(GH-8777) Reword here-string section for clarity

[michaeltlombardi]

PR Summary

This PR rewords the section of About Quoting Rules for clarity by being more explicit about the opening and closing tags and their effect.

• Resolves Quotation Marks Interpretation #8777

PR Context

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Cmdlet reference & about_ topics
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[opbld31]

Docs Build status updates of commit 2bd8185:

✅ Validation status: passed

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

For more details, please refer to the build report.

Note: Broken links written as relative paths are included in the above build report. For broken links written as absolute paths or external URLs, see the broken link report.

For any questions, please:

• Try searching the docs.microsoft.com contributor guides
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[sdwheeler]

See my suggestions.

[opbld33]

Docs Build status updates of commit 10a80c0:

✅ Validation status: passed

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

For more details, please refer to the build report.

Note: Broken links written as relative paths are included in the above build report. For broken links written as absolute paths or external URLs, see the broken link report.

For any questions, please:

• Try searching the docs.microsoft.com contributor guides
• Post your question in the Docs support channel

[opbld32]

Docs Build status updates of commit bad27e2:

✅ Validation status: passed

File	Status	Preview URL	Details
reference/5.1/Microsoft.PowerShell.Core/About/about_Quoting_Rules.md	✅Succeeded	View (powershell-5.1)
reference/7.0/Microsoft.PowerShell.Core/About/about_Quoting_Rules.md	✅Succeeded	View (powershell-7)
reference/7.1/Microsoft.PowerShell.Core/About/about_Quoting_Rules.md	✅Succeeded	View (powershell-7.1)
reference/7.2/Microsoft.PowerShell.Core/About/about_Quoting_Rules.md	✅Succeeded	View (powershell-7.2)
reference/7.3/Microsoft.PowerShell.Core/About/about_Quoting_Rules.md	✅Succeeded	View (powershell-7.3)

For more details, please refer to the build report.

Note: Broken links written as relative paths are included in the above build report. For broken links written as absolute paths or external URLs, see the broken link report.

For any questions, please:

• Try searching the docs.microsoft.com contributor guides
• Post your question in the Docs support channel