Job can not be purged when using the Java batch In-Memory Persistence

[Arunkumar-Kallyodan]

Describe the bug
When using memory persistence with java batch, jobs cannot be removed from the in-memory repository

Steps to Reproduce
Define a batch server with no batchPersistence defined so that it uses in-memory . Submit a jon and purge the job with the REST interface or batch Manager. A 500 error will occur and the job will not be removed from the in-memory repository. But the job logs will be deleted.

Expected behavior
When using the purge using the REST interface or batchManager, the job should be removed from the backing repository either using in-memory or database

Additional context
The limitation of using memory persistence is that if the server is stopped then the persistence is lost. However , a user should still be able to remove the data from the in-memory repository with a purge after this fix

[LifeIsGood524]

The PR is merged and is in a release build. Can this issue be closed? @dmbelina