[epic] Implement upgrade tests for OperatorController

[joelanford]

In order to have confidence that feature additions and bug fixes are reflected after an upgrade, we should add a suite of upgrade tests that:

1. Install the most recent public release.
2. Create objects that sufficiently exercise our API surface and behaviors.
3. Upgrade in place from the most recent public release to a build from the current commit.
4. Make assertions that prove that changes from the current commit are reflected.