[Improvement] Support Kerberos auth for Iceberg Rest Catalog with JDBC backend on HDFS storage

### What would you like to be improved?

Hello folks,
I would like to configure an Iceberg Rest Catalog with a JDBC backend (postgreSQL) and HDFS storage.
My HDFS needs a kerberos authentication.
Can you please add this authentication method for JDBC backend?
Thanks

### How should we improve?

Add Kerberos authentication method for JDBC backend and HDFS storage for Iceberg Rest Catalog

Start by locating the Iceberg REST Catalog JDBC backend and its HDFS storage authentication entry points, then inspect the existing authentication configuration and tests. Done means the JDBC backend and HDFS storage can be configured to authenticate with Kerberos for this catalog setup.

Written by the indexing model from the issue text.