fix(deps): update flyway/flyway docker tag to v10.21

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
flyway/flyway	container	minor	10.20 -> 10.21
flyway/flyway	final	minor	10.20 -> 10.21

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 69.83%. Comparing base (0c8a797) to head (837ecaa).
Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #271   +/-   ##
=======================================
  Coverage   69.83%   69.83%           
=======================================
  Files          13       13           
  Lines         305      305           
=======================================
  Hits          213      213           
  Misses         92       92           

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