[hotfix][mysql] Fix the binlog position didn't update when emit DDL (#925)

flink-connector-mysql-cdc/src/main/java/com/ververica/cdc/connectors/mysql/source/reader/MySqlRecordEmitter.java

@@ -89,6 +89,8 @@ public final class MySqlRecordEmitter<T>
                 splitState.asBinlogSplitState().recordSchema(tableChange.getId(), tableChange);
             }
             if (includeSchemaChanges) {
+                BinlogOffset position = getBinlogPosition(element);
+                splitState.asBinlogSplitState().setStartingOffset(position);
                 emitElement(element, output);
             }
         } else if (isDataChangeRecord(element)) {