[ENHANCE] Set log level in helm chart

[dabcoder]

Is your feature request related to a problem? Please describe.

Following https://github.com/stakater/Reloader/pull/638, it would be good to expose such log level configuration to the controller's helm chart (values file).

Describe the solution you'd like

It's already possible to configure the log format. Add an option for the log level as well.

Describe alternatives you've considered

None at this point.

Additional context

N/A.