fix(sink): fix starrocks sink array check

[xxhZs]

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What's changed and what's your intention?

In our implementation of starrocks sink, the type of the array stored in table nformation_schema.columns is UNKNOWN, which was recently fixed by starrocks, so we are fixing it as well, and we are still keeping UNKNOWN for the sake of compatibility with the old version.

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[wenym1]

LGTM