Fix unstable test changefeed_dup_error_restart

[hongyunyan]

What problem does this PR solve?

Issue Number: close #xxx

What is changed and how it works?

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Questions

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[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: asddongmen

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-03-12 01:48:24.737040673 +0000 UTC m=+320460.342569594: ☑️ agreed by asddongmen.

[ti-chi-bot]

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