Include basic Operator config in Operator guide as well as Config guide

 I have trouble finding the docs for this https://issues.redhat.com/browse/PROJQUAY-1090

They appear in config guide: https://access.redhat.com/documentation/en-us/red_hat_quay/3.6/html-single/configure_red_hat_quay/index#operator-volume-size-overrides

the configuration guide I would expect to be mostly about quay-level config which the volume size or env var overrides really are not