[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.*}

从 Apache Arrow Java 源代码中的 ListVector#setValueCount 开始，查看链接的拉取请求 apache/arrow#7214 以了解预期行为。跟踪当 valueCount 小于 lastSet 时数据向量的值计数是如何计算的，然后在可用的情况下运行相关的 ListVector 测试。完成的标准是：在这种情况下，内部向量接收到正确的计数。

由索引模型根据 Issue 内容生成。