tests(ticdc): fix bank test (#11407)

[ti-chi-bot]

This is an automated cherry-pick of #11407

What problem does this PR solve?

Issue Number: close #11806

What is changed and how it works?

Check List

Tests

• Integration test
• Manual test (add detailed scripts or steps below)
  

Questions

Will it cause performance regression or break compatibility?

Do you need to update user documentation, design documentation or monitoring documentation?

Release note

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[ti-chi-bot]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Please upload report for BASE (release-8.1@d0e23ef). Learn more about missing BASE report.

Additional details and impacted files

Components	Coverage Δ
cdc	61.7742% <0.0000%> (?)
dm	51.0561% <0.0000%> (?)
engine	63.4020% <0.0000%> (?)

Flag	Coverage Δ
unit	57.4019% <ø> (?)

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