[Java] ListVector's setValueCount does not set inner vector's value count correctly

In ListVector#setValueCount, we always compute data vector's value count based on lastSet - this is incorrect when valueCount is less than lastSet

**Reporter**: [Prudhvi Porandla](https://issues.apache.org/jira/browse/ARROW-8842) / @pprudhvi
#### PRs and other links:
- [GitHub Pull Request apache/arrow#7214](https://github.com/apache/arrow/pull/7214)

_{**Note**: *This issue was originally created as [ARROW-8842](https://issues.apache.org/jira/browse/ARROW-8842). Please see the [migration documentation](https://github.com/apache/arrow/issues/14542) for further details.*}

從 Apache Arrow Java 原始碼中的 ListVector#setValueCount 開始，查看連結的拉取請求 apache/arrow#7214 以了解預期行為。追蹤當 valueCount 小於 lastSet 時資料向量的值計數如何計算，然後在可用的情況下執行相關的 ListVector 測試。完成的標準是：在這種情況下，內部向量收到正確的計數。

由索引模型根據 Issue 內容生成。