Add a log message indicating that the restore is complete

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=171719014

java/google/registry/backup/RestoreCommitLogsAction.java

@@ -126,6 +126,7 @@ public class RestoreCommitLogsAction implements Runnable {
                             .setLastWrittenTime(entry.getValue())
                             .build())
             .append(CommitLogCheckpointRoot.create(lastCheckpoint.getCheckpointTime())));
+    logger.info("Restore complete");
   }
 
   /**