handle the timeout correctly

Author: tburch

src/main/java/com/lowtuna/jsonblob/core/BlobCleanupConsumer.java

@@ -31,6 +31,10 @@ public void run() {
     log.info("Polling queue for files to process for {}", QUEUE_TIMEOUT);
     try {
       File file = filesToProcess.poll(QUEUE_TIMEOUT.getQuantity(), QUEUE_TIMEOUT.getUnit());
+      if (file == null) {
+        log.info("Timed out after {} while waiting for something to come onto the queue", QUEUE_TIMEOUT);
+        return;
+      }
       log.debug("Processing {}", file.getAbsolutePath());
       String blobId = file.getName().split("\\.", 2)[0];
       File metadataFile = fileSystemJsonBlobManager.getMetaDataFile(file.getParentFile());