Improve Iceberg CI testing by leveraging standard catalogs

[lbooker42]

Our Iceberg implementation uses a custom-implemented Catalog to perform testing.

Since our implementation is catalog-agnostic, we can likely leverage an Iceberg API catalog provider (such as JDBC + Sqlite) to act as the test catalog. This would reduce maintenance and provide a more accurate testing environment locally and in CI.

[chipkent]

This should also allow Python methods to be unit tested.

[devinrsmith]

I've used https://github.com/xerial/sqlite-jdbc with success before.