Add support for Kuadrants AuthPolicy

[pehala]

Overview

This PR adds the ability to run (most of) the authoring tests on Kuadrant. The actual tests are mostly unchanged, but everything else had to change in some mostly minor ways. Currently, around 43 out of 106 tests run on Kuadrant, and many need code changes that will come in subsequent PRs.

Notable changes

• Add Route and Proxy interfaces
  • Kuadrant uses a different route and differently configured envoy than we do, so I added these interfaces to ensure compatibility with new Kuadrant classes.
  • Change some parameter types in said classes to ensure compatibility with the new ones.
• Add run_on_kuadrant fixture, which indicates that the test or module doesn't run on Kuadrant
• Add configuration options for Kuadrant deployment
  • It expects that Kuadrant and Gateway are already deployed.

[jsmolar]

Capabilities should be solved in another PR, right now I'm fine with a solution that leverages fixtures (#164)