*: check delete unique key's handle to handle corner case

[wjhuang2016]

What problem does this PR solve?

Issue Number: close #52914

Problem Summary:
Take the case from the issue, if an insert is executed during delete only, there is no record on the temporary index.
Before the merge process, a delete operation may delete the index key value(generated by ingest) unexpectedly.
To avoid this problem, we need to check if the delete value's handle is the same as we want to delete.
If not, it means that the value we want to delete is covered by another value already, which shouldn't be deleted again.

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.

fix a bug which may cause data consistency problem when adding unique index 

[codecov]

Codecov Report

Attention: Patch coverage is 67.85714% with 9 lines in your changes missing coverage. Please review.

Project coverage is 74.4937%. Comparing base (cc127c1) to head (70c4447).
Report is 1213 commits behind head on master.

Additional details and impacted files

@@               Coverage Diff                @@
##             master     #52975        +/-   ##
================================================
+ Coverage   74.4290%   74.4937%   +0.0647%     
================================================
  Files          1497       1518        +21     
  Lines        356920     447126     +90206     
================================================
+ Hits         265652     333081     +67429     
- Misses        71938      93644     +21706     
- Partials      19330      20401      +1071     

Flag	Coverage Δ
integration	49.3541% <67.8571%> (?)
unit	71.3687% <28.5714%> (-1.8315%)	⬇️

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

Components	Coverage Δ
dumpling	53.9957% <ø> (-2.3014%)	⬇️
parser	∅ <ø> (∅)
br	47.0120% <ø> (+4.0533%)	⬆️

[wjhuang2016]

/retest

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Benjamin2037, tangenta

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Needs approval from an approver in each of these files:

• OWNERS [Benjamin2037,tangenta]
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• pkg/table/OWNERS [Benjamin2037,tangenta]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-05-16 05:24:15.714360648 +0000 UTC m=+1717209.471496222: ☑️ agreed by Benjamin2037.
• 2024-05-16 06:15:50.429396385 +0000 UTC m=+1720304.186531958: ☑️ agreed by tangenta.

[wjhuang2016]

/retest

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-8.1: #53333.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-7.5: #53461.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-6.5: #53701.

[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch release-7.1: #56886.