planner: fix idxMergePartPlans forget to deal with RootTaskConds (#58507)

[ti-chi-bot]

This is an automated cherry-pick of #58507

What problem does this PR solve?

Issue Number: close #58476

Problem Summary:

What changed and how does it work?

fix idxMergePartPlans forget to deal with RootTaskConds

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 idxMergePartPlans forget to deal with RootTaskConds

修复在处理 idxMergePartPlans 时忘记处理 RootTaskConds 的问题

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: hawkingrei, winoros

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-01-23 09:29:49.022871908 +0000 UTC m=+345916.353791312: ☑️ agreed by hawkingrei.
• 2025-01-23 09:31:07.533831858 +0000 UTC m=+345994.864751259: ☑️ agreed by winoros.

[codecov]

Codecov Report

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Additional details and impacted files

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