Avoid 48 years delay at startup.

prometheus/src/main/java/com/alibaba/otter/canal/prometheus/impl/PrometheusCanalEventDownStreamHandler.java

@@ -13,7 +13,7 @@ import java.util.concurrent.atomic.AtomicLong;
  */
 public class PrometheusCanalEventDownStreamHandler extends AbstractCanalEventDownStreamHandler<List<Event>> {
 
-    private final AtomicLong latestExecuteTime  = new AtomicLong(0L);
+    private final AtomicLong latestExecuteTime  = new AtomicLong(System.currentTimeMillis());
     private final AtomicLong transactionCounter = new AtomicLong(0L);
     private final AtomicLong rowEventCounter    = new AtomicLong(0L);
     private final AtomicLong rowsCounter        = new AtomicLong(0L);