fix shrink char column in map/struct
before we has char with specific length defined in map or struct field
we select map or struct , the char column in which one has been padding if we just insert less than specific length chars
but in mysql here just show inserted chars not padding specific length chars
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Co-authored-by: yiguolei <676222867@qq.com>
Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
