Adds logging to DetectNewPartitionsAction in spanner changestream source. (#36290)

Author: acrites

sdks/java/io/google-cloud-platform/src/main/java/org/apache/beam/sdk/io/gcp/spanner/changestreams/action/DetectNewPartitionsAction.java

@@ -190,11 +190,13 @@ private void outputBatch(
           partition.toBuilder().setScheduledAt(scheduledAt).build();
 
       LOG.info(
-          "[{}] Outputting partition at {} with start time {} and end time {}",
+          "[{}] Outputting partition at {} with start time {}, end time {}, creation time {} and output timestamp {}",
           updatedPartition.getPartitionToken(),
           updatedPartition.getScheduledAt(),
           updatedPartition.getStartTimestamp(),
-          updatedPartition.getEndTimestamp());
+          updatedPartition.getEndTimestamp(),
+          createdAt,
+          minWatermark);
 
       receiver.outputWithTimestamp(partition, new Instant(minWatermark.toSqlTimestamp()));