[Fix](cdc) Fix the problem of converting the int2 and smallserial data types of the pg (#582)

Author: Aalron

flink-doris-connector/src/main/java/org/apache/doris/flink/tools/cdc/postgres/PostgresType.java

@@ -75,7 +75,7 @@ public static String toDorisType(String postgresType, Integer precision, Integer
         switch (postgresType) {
             case INT2:
             case SMALLSERIAL:
-                return DorisType.TINYINT;
+                return DorisType.SMALLINT;
             case INT4:
             case SERIAL:
                 return DorisType.INT;