expression: push down abs() to TiFlash (#24841)

[ti-srebot]

cherry-pick #24841 to release-5.0
You can switch your code base to this Pull Request by using git-extras:

# In tidb repo:
git pr https://github.com/pingcap/tidb/pull/25562

After apply modifications, you can push your change to this PR via:

git push git@github.com:ti-srebot/tidb.git pr/25562:release-5.0-a71586e6ca62

---

What problem does this PR solve?

Issue Number: close pingcap/tiflash#1937

Problem Summary:

What is changed and how it works?

Proposal: xxx

What's Changed: push down abs() to tiflash

How it Works:

Related changes

• PR to update pingcap/docs/pingcap/docs-cn:
• Need to cherry-pick to the release branch

Check List

Tests

• Integration test
• Manual test (add detailed scripts or steps below)

Release note

• push down abs() to TiFlash

[ti-chi-bot]

@ti-srebot: This cherry pick PR is for a release branch and has not yet been approved by release team.
Adding the do-not-merge/cherry-pick-not-approved label.

To merge this cherry pick, it must first be approved by the collaborators.

AFTER it has been approved by collaborators, please ping the release team in a comment to request a cherry pick review.

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[ti-srebot]

/run-all-tests

[ti-srebot]

@fzhedu you're already a collaborator in bot's repo.

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• lzmhhh123
• wshwsh12

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[fzhedu]

#25133 merged to 5.0