Add note about the need to patch docker images

[sdwheeler]

PR Summary

Add note about the need to patch docker images

• Fixes AB#292127

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.

[azure-boards]

✅ Successfully linked to Azure Boards work item(s):

• Task 292127

[learn-build-service-prod]

Learn Build status updates of commit aa6728a:

✅ Validation status: passed

File	Status	Preview URL	Details
reference/docs-conceptual/install/PowerShell-in-Docker.md	✅Succeeded	View (>=powershell-5.1)
reference/includes/alpine-support.md	✅Succeeded	View (>=powershell-5.1)
reference/includes/debian-support.md	✅Succeeded	View (>=powershell-5.1)
reference/includes/rhel-support.md	✅Succeeded	View (>=powershell-5.1)
reference/includes/ubuntu-support.md	✅Succeeded	View (>=powershell-5.1)

For more details, please refer to the build report.

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