[cherry-pick] Refactor the migration cases.

[blackpiglet]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 59.12%. Comparing base (2b8b6dc) to head (6f7704a).
Report is 2 commits behind head on release-1.15.

Additional details and impacted files

@@              Coverage Diff              @@
##           release-1.15    #8533   +/-   ##
=============================================
  Coverage         59.12%   59.12%           
=============================================
  Files               367      367           
  Lines             39118    39118           
=============================================
  Hits              23130    23130           
  Misses            14520    14520           
  Partials           1468     1468           

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