The BatchUtils doesn't purge data in all tables

[scottkurz]

When using BatchSPIManager.getInstance().getBatchJobUtil().purgeOwnedRepositoryData(tagName);

Then "CheckPoint" table was never cleared, although this table is for batch internal use, but it will leave a lot of garbage data over the time.

So this table should also be cleared after calling the API.

(Opened by haotian@java.net..thanks)