Unit tests get_all_tables needs to be skipped because Pandas backend does not support list_databases #1788

Describe the bug
The test test_get_all_tables has to be skipped in Ibis 7.1 because there is no support for list_databases on a pandas client. Please see here.

In a future release when we support DuckDB for in memory tables, this unit test can be set up to list databases in duckDB.

What type of connections are you using for source and target?
Unit Test