Add scheduled queries in Redshift serverless

Scheduling a query on Redshift can be useful for example to refresh an incremental materialized views on an external table from the lake. It requires [some configuration](https://docs.aws.amazon.com/redshift/latest/mgmt/query-editor-schedule-query.html) that DSF can abstract and simplify.

Start by reviewing the linked AWS Redshift query scheduling configuration and the DSF repository entry points for Redshift resources. Define the required abstraction and its expected configuration, then verify that a scheduled query can refresh an incremental materialized view on an external lake table.

Written by the indexing model from the issue text.