Task org.apache.jackrabbit.oak.commons.concurrent.NotifyingFutureTask@1a5ac41d[Not completed, task = org.apache.jackrabbit.oak.spi.commit.BackgroundObserver$1$1@1e655309] rejected from java.util.concurrent.ThreadPoolExecutor@7a4ea134[Shutting down, pool size = 1, active threads = 1, queued tasks = 0, completed tasks = 4]