[Flink]fix NullPointerException in log output and Kerberos authentica…

[lklhdu]

Resolve #475 #472

When reading the Filestore of the Arctic table using Flink, it triggers a Kerberos authentication Exception and a log-related NullPointerException, which needs to be fixed.)

Brief change log

• Add Kerberos authentication operation when reading data
• Replaces the field obtained when printing the log

How was this patch tested?

• [ ] Add some test cases that check the changes thoroughly including negative and positive cases if possible

• [ ] Add screenshots for manual tests if appropriate

• [x] Run test locally before making a pull request