*: add data type default values

[zimulala]

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• Other reference link(s):
  This feature issue: Data type default values support some expressions tidb#50936

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[LGTM Timeline notifier]

Timeline:

• 2024-03-06 03:20:45.919606929 +0000 UTC m=+223672.941853316: ☑️ agreed by tangenta.
• 2024-03-06 07:03:59.437550646 +0000 UTC m=+237066.459797034: ☑️ agreed by hfxsd.

[hfxsd]

/approve

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