Omit service account generation in Helm Chart when not using Strimzi auto detection

[seglo]

A service account is only required when using the Strimzi watcher so that a ClusterRole can be bound to it. When the Strimzi watch is disabled, do not generate a service account and remove the service account binding in the Deployment spec.

[khorshuheng]

May I pick this up?

[seglo]

@khorshuheng Certainly.

For this issue I was thinking that we could make the service account optional during install. It's required when Strimzi is installed, so that we may assign it the appropriate roles, but it may also be useful in non-Strimzi installs if users don't want to use the default service account of a namespace.

We could add helm configuration with a default state of:

serviceAccount:
  create: false
  name: kafka-lag-exporter-serviceaccount

For the resource template itself we could use an or expression to create the resource when either the Strimzi watcher is enabled, or when serviceAccount.create == true. We will also need to optionally add the serviceAccount field in the Deployment template spec.

[seglo]

Also, if you (or any of your colleagues) have any of your own ideas for the project please feel free to create an issue with a design for discussion.

[seglo]

Implemented in #64