Update Kubernetes Cluster controller and add support for meta.externalName

[vladfr]

I ran into this problem that cluster updates are never performed. While trying to debug I actually made good headway.

The problem is that the Kubernetes Civo API changed quite a bit, and now only works via Cluster ID (which makes a ton of sense). The current controller for clusters has two problems:

• does not use the api properly
• cannot remember the Civo ID of the cluster, so it never finds the clusters it creates

Changes:

• it's now using the proper civo API client
• the cluster k8s object now remembers the Civo ID via meta
  • the controller uses the Civo ID in every API operation
  • Updates work too!

Fixes #41

I have:

• [x] Read and followed Crossplane's contribution process.
• [x] Run make reviewable test to ensure this PR is ready for review.

Tests

• [x] Added tests for create and update.

Open issues

• currently, the API doesn't allow updating the firewall ID. The code handles this update, but the underlying resource doesn't actually get updated.
• applications aren't updated or removed.

NOTE: I've bumped /build to latest, since I couldn't run make generate anymore.

[vladfr]

Applications are being installed on Create, but not added on Update.

App name is civo-cluster-autoscaler. If it's specified when Creating, it works and the app appears on the CIVO Dashboard. If you then do an Update, this is the API error:

{"level":"warning","msg":"update error:Error: Unknown error response - status: 404 Not Found, code: 404, reason: {\"code\":\"database_kubernetes_aplication_not_found\",\"reason\":\"Failed to find the Kubernetes application for installation\"}\n ","time":"2023-03-21T16:56:28+02:00"}

[vladfr]

I'd like to leave a note here. The Observe() cycle should not trigger any modifications. It should return an ExternalObservation, and the reconciler will call Update when needed.

Previously the code would call Update and trigger resource updates. This made it so that the reconciler never issued proper log messages. With this change, you can clearly see when the reconciler requests a Create or Update; or whenever it sees an error.