load_data: fix the bug that column list does not work in load data. (#35222)

[ti-srebot]

cherry-pick #35222 to release-5.4
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# In tidb repo:
git pr https://github.com/pingcap/tidb/pull/35464

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---

What problem does this PR solve?

Issue Number: close #35198

Problem Summary:

What is changed and how it works?

As the issue describes, the column list does not work in load data.

This is caused by that in initLoadColumns, e.insertColumns is appended according to the order of the table columns, not the order of the column list.

Check List

Tests

• Integration test

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

Fix the issue that column list does not work in load data.

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• cfzjywxk
• youjiali1995

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[ti-srebot]

/run-all-tests

[cfzjywxk]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 515986e

[cfzjywxk]

/merge

[sre-bot]

Code Coverage Details: https://codecov.io/github/pingcap/tidb/commit/caad8aab7244e35e07705358845c9d5445639284

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