flashback: fix realtikvtest/flashbacktest test cases (#52899)

[ti-chi-bot]

This is an automated cherry-pick of #52899

What problem does this PR solve?

Issue Number: close #52898

Problem Summary: After #52285, flashbacktest alwayws failed with error info like

[r="assert failed, schemaID should not be 0, please set it when creating the event"]
[stack="[github.com/pingcap/tidb/pkg/util.Recover](http://github.com/pingcap/tidb/pkg/util.Recover)
	/home/genius/project/src/[github.com/pingcap/tidb/pkg/util/misc.go:118](http://github.com/pingcap/tidb/pkg/util/misc.go:118)
runtime.gopanic
	/home/genius/project/go/src/runtime/panic.go:914
[github.com/pingcap/tidb/pkg/util/intest.doPanic](http://github.com/pingcap/tidb/pkg/util/intest.doPanic)
	/home/genius/project/src/[github.com/pingcap/tidb/pkg/util/intest/assert.go:59](http://github.com/pingcap/tidb/pkg/util/intest/assert.go:59)
[github.com/pingcap/tidb/pkg/util/intest.Assert](http://github.com/pingcap/tidb/pkg/util/intest.Assert)
	/home/genius/project/src/[github.com/pingcap/tidb/pkg/util/intest/assert.go:27](http://github.com/pingcap/tidb/pkg/util/intest/assert.go:27)
[github.com/pingcap/tidb/pkg/statistics/handle/util.(*DDLEvent).IsMemOrSysDB](http://github.com/pingcap/tidb/pkg/statistics/handle/util.(*DDLEvent).IsMemOrSysDB)
	/home/genius/project/src/[github.com/pingcap/tidb/pkg/statistics/handle/util/ddl_event.go:51](http://github.com/pingcap/tidb/pkg/statistics/handle/util/ddl_event.go:51)
[github.com/pingcap/tidb/pkg/statistics/handle/ddl.(*ddlHandlerImpl).HandleDDLEvent](http://github.com/pingcap/tidb/pkg/statistics/handle/ddl.(*ddlHandlerImpl).HandleDDLEvent)
	/home/genius/project/src/[github.com/pingcap/tidb/pkg/statistics/handle/ddl/ddl.go:58](http://github.com/pingcap/tidb/pkg/statistics/handle/ddl/ddl.go:58)
[github.com/pingcap/tidb/pkg/domain.(*Domain).updateStatsWorker](http://github.com/pingcap/tidb/pkg/domain.(*Domain).updateStatsWorker)
	/home/genius/project/src/[github.com/pingcap/tidb/pkg/domain/domain.go:2415](http://github.com/pingcap/tidb/pkg/domain/domain.go:2415)
[github.com/pingcap/tidb/pkg/domain.(*Domain).UpdateTableStatsLoop.func3](http://github.com/pingcap/tidb/pkg/domain.(*Domain).UpdateTableStatsLoop.func3)
	/home/genius/project/src/[github.com/pingcap/tidb/pkg/domain/domain.go:2235](http://github.com/pingcap/tidb/pkg/domain/domain.go:2235)
[github.com/pingcap/tidb/pkg/util.(*WaitGroupEnhancedWrapper).Run.func1](http://github.com/pingcap/tidb/pkg/util.(*WaitGroupEnhancedWrapper).Run.func1)
	/home/genius/project/src/[github.com/pingcap/tidb/pkg/util/wait_group_wrapper.go:99](http://github.com/pingcap/tidb/pkg/util/wait_group_wrapper.go:99)"]

What changed and how does it work?

Check List

Tests

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

  • I checked and no code files have been changed.

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Defined2014, hi-rustin

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• OWNERS [Defined2014,hi-rustin]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-08-08 03:15:00.973488591 +0000 UTC m=+494630.840587677: ☑️ agreed by Defined2014.
• 2024-08-08 03:17:07.180095193 +0000 UTC m=+494757.047194279: ☑️ agreed by hi-rustin.

[codecov]

Codecov Report

Attention: Patch coverage is 84.21053% with 3 lines in your changes missing coverage. Please review.

Please upload report for BASE (release-8.1@370bd5a). Learn more about missing BASE report.

Additional details and impacted files

@@               Coverage Diff                @@
##             release-8.1     #55288   +/-   ##
================================================
  Coverage               ?   71.1634%           
================================================
  Files                  ?       1466           
  Lines                  ?     422679           
  Branches               ?          0           
================================================
  Hits                   ?     300793           
  Misses                 ?     101368           
  Partials               ?      20518           

Flag	Coverage Δ
unit	71.1634% <84.2105%> (?)

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

Components	Coverage Δ
dumpling	52.9656% <0.0000%> (?)
parser	∅ <0.0000%> (?)
br	41.3451% <0.0000%> (?)

[Defined2014]

/retest