Task org.apache.jackrabbit.oak.commons.concurrent.NotifyingFutureTask@48160b96[Not completed, task = org.apache.jackrabbit.oak.spi.commit.BackgroundObserver$1$1@64ce51a] rejected from java.util.concurrent.ThreadPoolExecutor@74fbe9c3[Shutting down, pool size = 1, active threads = 1, queued tasks = 0, completed tasks = 6]