Change description of ONLY_FULL_GROUP_BY (#15416)

[ti-chi-bot]

This is an automated cherry-pick of #15416

Change Description of ONLY_FULL_GROUP_BY

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What is changed, added or deleted? (Required)

Change description of ONLY_FULL_GROUP_BY Chinese version, the previous description is wrong
修改 ONLY_FULL_GROUP_BY 部分的描述，原有的描述与实际不一致

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• v7.5 (TiDB 7.5 versions)
• v7.4 (TiDB 7.4 versions)
• v7.3 (TiDB 7.3 versions)
• v7.1 (TiDB 7.1 versions)
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• v6.1 (TiDB 6.1 versions)
• v5.4 (TiDB 5.4 versions)
• v5.3 (TiDB 5.3 versions)
• v5.2 (TiDB 5.2 versions)
• v5.1 (TiDB 5.1 versions)
• v5.0 (TiDB 5.0 versions)

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• Delete files
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[Oreoxmt]

/approve

[ti-chi-bot]

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