Verification of continuous ingest with agitation should check for orphaned files

Original Jira ticket: [ACCUMULO-4748](https://issues.apache.org/jira/browse/ACCUMULO-4748)

We have found instances where files are being orphaned but we have not as of writing this ticket figured out why. We should however expand the continuous ingest verification to check for orphaned files which we hypothesize will show up when agitation is when running continuous ingest.

首先，在 repository 中定位 continuous ingest 验证以及与其相关的 agitation 测试或入口点。运行现有验证，以了解如何观察 orphaned files，然后与 maintainers 确定检查条件和测试条件。当该验证能够在 agitation 期间可靠地报告 orphaned files 时，即表示完成。

由索引模型根据 Issue 内容生成。