- Add new optional ytt params for the Supervisor deployment.
- When the Supervisor is making calls to an upstream OIDC provider,
use these variables if they were provided.
- These settings are integration tested in the main CI pipeline by
sometimes setting them on deployments in certain cases, and then
letting the existing integration tests (e.g. TestE2EFullIntegration)
provide the coverage, so there are no explicit changes to the
integration tests themselves in this commit.