planner: remove useless code

[hawkingrei]

What problem does this PR solve?

Issue Number: close #xxx

Problem Summary:

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 ✅

Project coverage is 74.4824%. Comparing base (acdb6f5) to head (01d2945).
Report is 4 commits behind head on master.

Additional details and impacted files

@@               Coverage Diff                @@
##             master     #53280        +/-   ##
================================================
+ Coverage   72.4943%   74.4824%   +1.9880%     
================================================
  Files          1493       1494         +1     
  Lines        429359     430676      +1317     
================================================
+ Hits         311261     320778      +9517     
+ Misses        98889      89966      -8923     
- Partials      19209      19932       +723     

Flag	Coverage Δ
integration	49.2540% <ø> (?)
unit	71.2421% <ø> (-0.1547%)	⬇️

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

Components	Coverage Δ
dumpling	53.9957% <ø> (ø)
parser	∅ <ø> (∅)
br	50.2175% <ø> (+8.7605%)	⬆️

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

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

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• pkg/planner/OWNERS [AilinKid,hi-rustin]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2024-05-15 06:53:31.810731967 +0000 UTC m=+1636165.567867537: ☑️ agreed by hi-rustin.
• 2024-05-15 08:05:41.86628844 +0000 UTC m=+1640495.623424011: ☑️ agreed by AilinKid.