v8.5.4: MySQL compatibility about decimal insert through jdbc

[ChangRui-Ryan]

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[qiancai]

Rest LGTM

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2025-11-05 00:59:00.768911352 +0000 UTC m=+231790.211941221: ☑️ agreed by hfxsd.
• 2025-11-05 07:32:30.207083996 +0000 UTC m=+255399.650113875: ☑️ agreed by qiancai.

[hfxsd]

/approve

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[ti-chi-bot]

In response to a cherrypick label: new pull request created to branch master: #21351.