Required changes after upgrading postgres jdbc driver to 42.3.3

[majguo]

Description

This PR targets to fix the new issues after upgrading postgres jdbc driver to 42.3.3 which was introduced by #12, #13, #14, #15 and #16.

Change summary:

• Change to postgresql-42.3.3.jar in Dockerfile
• Workaround ssl certificate restriction after upgrading postgres jdbc driver to 42.3.3 (see Support of Postgres Jdbc driver version >= 42.2.5 cloudcaptainsh/cloudcaptain#234 for more info):

  Internal Exception: java.sql.SQLException: Could not open SSL root certificate file //.postgresql/root.crt
  

Signed-off-by: Jianguo Ma [email protected]

[zhengchang907]

LGTM