warningLogs
If you want enable warning-logs to be logged, provide a lambda here.
Per default (or when passing null as sink here), warning-logs will not be logged.
It's your discretion whether you want warning-level logs in your debug / production app logged to somewhere or not.
Return
this to chain calls.
Parameters
sink
The lambda which gets invoked to write the warning-level logs to, or null to disable warning logging.