## Changes
While looking into adding variable lookups for notification destinations
([API][API]), I found the codegen approach for different classes of
variable lookups a bit complex. The template had a custom field override
(for service principals), the package had an override for the cluster
lookup, and it didn't produce tests.
The notification destinations API uses a default page size of 20 for
listing. I want to use a larger page size to limit the number of API
calls, so that would imply another customization on the template or a
manual override.
This code being rather mechanical, I used copilot to produce all
instances of the resolvers and their tests (after writing one of them
manually).
[api]: https://docs.databricks.com/api/workspace/notificationdestinations
## Tests
* Unit tests pass
* Manual confirmation that lookups of warehouses still work