*: update defalut value for expression

[zimulala]

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• [x] I've signed Contributor License Agreement that's required for repo owners to accept my contribution.

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• [x] v8.1 (TiDB 8.1 versions)
• [ ] v8.0 (TiDB 8.0 versions)
• [ ] v7.6 (TiDB 7.6 versions)
• [ ] v7.5 (TiDB 7.5 versions)
• [ ] v7.1 (TiDB 7.1 versions)
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• [ ] v5.1 (TiDB 5.1 versions)

What is the related PR or file link(s)?

• This PR is translated from:
• Other reference link(s): https://github.com/pingcap/tidb/pull/52677

Do your changes match any of the following descriptions?

• [ ] Delete files
• [ ] Change aliases
• [ ] Need modification after applied to another branch
• [ ] Might cause conflicts after applied to another branch

[ti-chi-bot[bot]]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[LGTM Timeline notifier]

Timeline:

• 2024-04-23 03:29:06.2323439 +0000 UTC m=+58102.972246812: :ballot_box_with_check: agreed by hfxsd.
• 2024-04-25 03:08:08.331924204 +0000 UTC m=+229645.071827115: :ballot_box_with_check: agreed by lilin90.

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[hfxsd]

/approve

[ti-chi-bot[bot]]

[APPROVALNOTIFIER] This PR is APPROVED

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