Highly available controller

[jlevesy]

What needs to be done?

The kudo controller app runs currently both the controller loops as wll as the webhook handler, and this constitutes a spof for webhook admission if we only have one replica.

While I not super keen to split this into two different deployment (but that's up for debate), it would be interesting to leverage k8s leader election capabilities so we could have multiple replicas of kudo running, but only one executing the control loop.

Acceptance Criteria

• You can scale the kudo deployment to as many replica as you wish, yet only one runs the control loop
• Helm chart deploys 2 replias by default
• e2e test suites are adapted