Provide better e2e-testing instructions [#12]

The "get a kubernetes cluster" part could use some outfleshing, but this
is certainly more straightforward than it was before.

.drone.yml

@@ -30,12 +30,3 @@ steps:
       dockerfile: Dockerfile
     when:
       event: [ tag, push ]
-
-  # Example configuration for publishing to a local registry for testing.
-  # - name: publish_locally
-  #   image: plugins/docker
-  #   settings:
-  #     dockerfile: Dockerfile
-  #     insecure: true
-  #     registry: 0.0.0.0:5000
-  #     repo: 0.0.0.0:5000/drone-helm3