Django-snowflake

* Fixed `EXISTS` subqueries by removing `LIMIT 1` (which Snowflake does not
support) from them.

* Fixed data corruption of new model instance IDs. Connection initialization
now sets `NOORDER_SEQUENCE_AS_DEFAULT=False` (after [the default
changed to True](https://docs.snowflake.com/en/release-notes/bcr-bundles/2024_01/bcr-1483)
in behavior change bundle 2024_01) to allow this backend to continue to
retrieve the ID of newly created objects using
`SELECT MAX(pk_name) FROM table_name`.

* Fixed crash in `DatabaseIntrospection.get_table_description()` due to
Snowflake adding a column to the output of `DESCRIBE TABLE` in behavior
change bundle 2023_08.

Initial release for Django 5.0.x.