Create CR for Sink

[gioppoluca]

Is your feature request related to a problem?
Have the Sink managed as a CR

Describe the solution you'd like
The need is to allow Robusta to watch namespaces to see watch for new Sinck CR and add them to its configuration thus removimg the hard coded configuration in Robusta deployment and the need to redeploy Robusta at each sink change

Describe alternatives you've considered
No alternative exists apart having to mix sink lifecycle with Robusta lifecycle that is not the best option

Additional context
NA