[Track 2 migration] Migrate dms-preview in extension

[jsntcy]

Migrate dms-preview in extension to track 2 SDK.

Thanks for the feedback! We are routing this to the appropriate team for follow-up. cc @radjaram, @kavitham10.

Issue Details

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Migrate dms-preview to track 2 SDK.

Author:	jsntcy
Assignees:	jsntcy
Labels:	Data Migration, Service Attention, Track 2 Migration, feature-request
Milestone:	Aug 2021 (2021-09-07)

[yonzhan]

Track 2 migration

[jsntcy]

Migrated in Azure/azure-cli-extensions#3740