Automated matrix integration tests

[ozamosi]

There should be a test suite that is able to:

• Set up a test environment (say, latest flux, latest k8s, always in kind)
• Install flux + a bunch of test resources
• Run "interesting" queries against the gitops backend, and record the responses.
• Then, for every version of flux and k8s we support:
  • Create a test environment running that
  • Install the same test resources
  • Check that the responses "match".

The definition of "match" is a bit complicated - it needs to be driven by what the frontend needs and expects, and some fields (e.g. dates) just won't match.

Because the data is being interpreted by js, I think we need to drive this suite from js.