Re-enable dependency search integration tests
Created by: mrnugget
This re-enables the dependency search integration tests that are now dependent on lockfile indexing.
The tests now configure site-config to allow global lockfile indexing and then add a policy to index lockfiles of the repositories for which we want to run dependency searches.
Ideally we'd have something like #37619 for them to run faster.
Test plan
- This is an integration test
