fix issue #4267 old和data长度不一样而产生的下标越界异常 (#4504)

connector/core/src/main/java/com/alibaba/otter/canal/connector/core/producer/MQMessageUtils.java

@@ -433,9 +433,7 @@ public class MQMessageUtils {
                             }
                         }
                         // update操作将记录修改前的值
-                        if (!rowOld.isEmpty()) {
-                            old.add(rowOld);
-                        }
+                        old.add(rowOld);
                     }
                 }
                 if (!sqlType.isEmpty()) {