Change metrics-bind-address default value to 0

[edif2008]

Summary

As part of the upgrading to Operator SDK 1.38.0, the default value for metrics-bind-address flag changed from 8080 to 0 to have the metrics service disabled by default. In #211, we didn't make this change to be backwards-compatible.

Tasks to be done

• Change the default value of metrics-bind-address to 0 when willing to make a new major release of the operator.