[Java][Docs] Document the use of the batchSize argument in Dataset ScanOptions

Several ScanOptions methods take a batchSize argument as shown: 

`public ScanOptions(long batchSize) {`
`    this(batchSize, Optional.empty());`
``}

Since the scanner reads one ArrowRecordBatch per load invocation, setting the parameter to a size larger than the RecordBatch has no effect. It only works when it's smaller than the number of rows in the RecordBatch, (i.e., the number or records read is equal to min(batchSize, recordBatch rowCount), potentially leading to some confusion. 

**Reporter**: [Larry White](https://issues.apache.org/jira/browse/ARROW-17346) / @lwhite1

_{**Note**: *This issue was originally created as [ARROW-17346](https://issues.apache.org/jira/browse/ARROW-17346). Please see the [migration documentation](https://github.com/apache/arrow/issues/14542) for further details.*}

Comece pelos métodos de Dataset ScanOptions que aceitam batchSize e rastreie como o scanner carrega um ArrowRecordBatch por invocação. Documente que valores maiores que a contagem de linhas do RecordBatch não têm efeito adicional, enquanto valores menores limitam os registros a min(batchSize, recordBatch rowCount); considera-se concluído quando a documentação de ScanOptions deixa esse comportamento claro.

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