[Bug] [chunjun-connection] 数据库字段为null时，同步空指针

[kinoxyz1]

Search before asking

• I had searched in the issues and found no similar issues.

What happened

当source为doris表，有如下一下记录时

INSERT INTO `` VALUES (2, 202231, 176, '0', NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, 198009.3600, 37780.8500, NULL, 738305.4300, 499126.9500, 4511, 948, NULL, 13017, 9824, 3.2094, 43.8948, 39.8532, NULL, 56.7186, 50.8069, '2022-07-28 06:02:20');

doris -> mysql 会空指针

What you expected to happen

可能是在数据类型转换的时候，没有做空值处理

How to reproduce

上面有建表语句，可以直接运行

Anything else

No response

Version

master

Are you willing to submit PR?

• Yes I am willing to submit a PR!

Code of Conduct

• I agree to follow this project's Code of Conduct