Move operator's CA Secret management outside of the operator

[pmalek]

Problem statement

Currently in the operator caManager is responsible for creating the CA certificate Secret for the operator.

This Secret is not removed when the operator is deleted.

As KO 2.0 is moving towards helm self signed certs and cert-manager integration, it might be a good idea to use these mechanism to manage that Secret.

Acceptance criteria

• As a user I can use helm self signed certs or cert-manager integration to create and manage operator's CA certificate
• No Secret leftover is left behind when operator is uninstalled.