ddl: remove useless field in temporaryIndexRecord (#50202)

[ti-chi-bot]

This is an automated cherry-pick of #50202

What problem does this PR solve?

Issue Number: close #50203

Problem Summary:
Found it when trying to close #49940 .

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

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Please upload report for BASE (release-7.5@f5f7f3e). Learn more about missing BASE report.

Additional details and impacted files

@@               Coverage Diff                @@
##             release-7.5     #55449   +/-   ##
================================================
  Coverage               ?   71.9905%           
================================================
  Files                  ?       1413           
  Lines                  ?     411693           
  Branches               ?          0           
================================================
  Hits                   ?     296380           
  Misses                 ?      95422           
  Partials               ?      19891           

Flag	Coverage Δ
unit	71.9905% <ø> (?)

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

Components	Coverage Δ
dumpling	52.9400% <0.0000%> (?)
parser	∅ <0.0000%> (?)
br	53.4850% <0.0000%> (?)

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: tangenta

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-09-27 04:20:12.203179431 +0000 UTC m=+1798881.943603365: ☑️ agreed by tangenta.

[ti-chi-bot]

This cherry pick PR is for a release branch and has not yet been approved by triage owners.
Adding the do-not-merge/cherry-pick-not-approved label.

To merge this cherry pick:

1. It must be approved by the approvers firstly.
2. AFTER it has been approved by approvers, please wait for the cherry-pick merging approval from triage owners.

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