[Improvement] Username and password should not be displayed in plaintext when loading catalogs

### What would you like to be improved?

Plaintext is dangerous and can't be applied in production, we should encode those information when loading catalogs from Gravitino

### How should we improve?

_No response_

No source file or test is named in the issue. Start by tracing the catalog-loading entry point and how usernames and passwords are displayed, then identify the existing tests for catalog loading; done means credentials are no longer shown in plaintext while catalogs continue to load successfully.

Written by the indexing model from the issue text.