File versions article is finally created

[MetMS2023]

1. create the article
2. update toc
3. remove redirection

[learn-build-service-prod]

Learn Build status updates of commit a063f10:

💡 Validation status: suggestions

File	Status	Preview URL	Details
migration/file-versions.md	💡Suggestion		Details
.openpublishing.redirection.json	✅Succeeded
migration/TOC.yml	✅Succeeded

migration/file-versions.md

• Line 20, Column 14: [Suggestion: duplicate-descriptions - See documentation] Attribute 'description' with value 'Learn about the transition plan of Migration Manager with a more scalable backend infrastructure.' is duplicated in 'file-versions.md(20,14)', 'new-migration-transition.md(20,14)'.

For more details, please refer to the build report.

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