Enable version controlling for SiddhiProcess CR objects

[BuddhiWathsala]

Purpose

Resolve #42

Goals

Previously SiddhiProcesses were unable to support version control. Here we enable version controlling in SiddhiProcess level.

Approach

Previously we have used the Client.Create() function in the controller-runtime client. Here we replace that function with controllerutil.CreateOrUpdate() function. The new function creates a k8s object if it isn't available. Otherwise, it gracefully updates the k8s object according to the mutate function that embedded to each k8s creation.

Automation tests

• Unit tests

  Update the unit tests

Test environment

minikube version: v1.2.0

Learning

From this change users can also change a stateful app to stateless and vice versa without any problem.