chore(notes): simplify post-install steps for ClusterIP service case

[tthvo]

Related to #177, #160

Descriptions

• Simplify post-install steps for ClusterIP service case.
• Use generic word application to refer to Cryostat in release notes. I suppose installing Cryostat chart already means installing Cryostat (See ci(oci): helm repackaging #177 (comment))

Motivations

When installing the chart without further customizations, the user just needs to port-forward the local port to the application pod. Previously, there were some extra steps that only defined some environment variables (i.e. not actually configuring cryostat).

How to test

helm install cryostat-sample charts/cryostat

Expected notes:

NOTES:

1. Configure the application to serve external traffic:
  ```
  No actions required with this configuration.
  ```

2. Forward local port to the application's pod:
  ```
  kubectl -n default wait --for=condition=available --timeout=60s deploy/cryostat-sample

  export POD_NAME=$(kubectl get pods -n default -l "app.kubernetes.io/name=cryostat,app.kubernetes.io/instance=cryostat-sample" --sort-by=.metadata.creationTimestamp -o jsonpath="{.items[-1:].metadata.name}")
  export CONTAINER_PORT=$(kubectl get pod -n default $POD_NAME -o jsonpath="{.spec.containers[0].ports[0].containerPort}")
  kubectl -n default port-forward $POD_NAME "8080:$CONTAINER_PORT"
  ```

3. Visit the application at:
  ```
  http://localhost:8080
  ```