executor: fix the wrong output when the whole data of partition table falls in one region

[winoros]

What problem does this PR solve?

Issue Number: close #41801

Problem Summary:

What is changed and how it works?

Our quick fix on the order prop push down for partitioned table miss the corner case for index scan.

Check List

Tests

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

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 that the IndexReader's result on partitioned table might be wrong when the whole data of the partitioned table is in one region.

[ti-chi-bot]

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[winoros]

#42024 This one is the final solution.
This pr just want to do a quick fix.

[winoros]

/retest-required

[ti-chi-bot]

@winoros: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
idc-jenkins-ci-tidb/unit-test	179ac09	link	true	/test unit-test

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[winoros]

This pr is target to be merged in minor version.

[ti-chi-bot]

@winoros: PR needs rebase.

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[winoros]

There's a perfect improvement on the master branch. Close this.