puller: fix a bug that may cause error when replicate truncate table ddl

[asddongmen]

What problem does this PR solve?

Issue Number: close #11765

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

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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[asddongmen]

/test all

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 55.1708%. Comparing base (6fc5a49) to head (ecd1a3a).
Report is 47 commits behind head on master.

Additional details and impacted files

Components	Coverage Δ
cdc	59.5992% <100.0000%> (-1.6109%)	⬇️
dm	50.0654% <ø> (-0.9801%)	⬇️
engine	53.2167% <ø> (-10.1572%)	⬇️

Flag	Coverage Δ
unit	55.1708% <100.0000%> (-2.2954%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

@@               Coverage Diff                @@
##             master     #11772        +/-   ##
================================================
- Coverage   57.4662%   55.1708%   -2.2954%     
================================================
  Files           851       1002       +151     
  Lines        126462     137404     +10942     
================================================
+ Hits          72673      75807      +3134     
- Misses        48389      56056      +7667     
- Partials       5400       5541       +141     

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• Flaky Tests Detection - Detect and resolve failed and flaky tests
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[ti-chi-bot]

@asddongmen: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
pull-cdc-integration-storage-test	ecd1a3a	link	true	/test cdc-integration-storage-test
pull-cdc-integration-mysql-test	ecd1a3a	link	true	/test cdc-integration-mysql-test
pull-cdc-integration-kafka-test	ecd1a3a	link	true	/test cdc-integration-kafka-test
pull-cdc-integration-pulsar-test	ecd1a3a	link	true	/test cdc-integration-pulsar-test

Full PR test history. Your PR dashboard.

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