fix: extra metrics handler

[guicassolato]

Options for the extra metrics handler of the controller manager need to be set before creating the manager.
Otherwise, the /server-metrics endpoint will not be included and return a 404.

Verification steps

make local-setup FF=1
kubectl port-forward service/authorino-controller-metrics 8080:8080 2>&1 >/dev/null &
curl http://localhost:8080/server-metrics

You should see the server metrics and not a 404 Not Found.

[adam-cattermole]

lgtm, verified on main receive a 404 page not found, whereas from these changes successfully retrieves the metrics.