Prevent ClickHouseConnection#prepareStatement(String, int) from throwing exception for Statement.RETURN_GENERATED_KEYS

[linghengqian]

Summary

• Fixes ClickHouseConnection#prepareStatement(String, int) should not throw an exception when Statement.RETURN_GENERATED_KEYS is recognized #1968 .
• Prevent ClickHouseConnection#prepareStatement(String, int) from throwing exception for Statement.RETURN_GENERATED_KEYS.

Checklist

Delete items not relevant to your PR:

• Unit and integration tests covering the common scenarios were added
• A human-readable description of the changes was provided to include in CHANGELOG
• For significant changes, documentation in https://github.com/ClickHouse/clickhouse-docs was updated with further explanations or tutorials

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