When the test suite runs, it leaves directories in the project root:

ObjectStore
└── ShadowNoFileLockStore
    └── defaultStore
        └── Recovery
            └── TransactionStatusManager
PutObjectStoreDirHere/
└── ShadowNoFileLockStore
    └── defaultStore

This is likely related to the transaction manager in some way. It should be configured to write these files somewhere under target.