Goal: Feature parity between KRP and Oauth-proxy. 

Features listed below: 

As part of the rbac configuration for https://github.com/openshift/oauth-proxy users could define a "verb" at the top level for an rbac expression. For example ...

--openshift-sar={"namespace": "NAMESPACE", "resource": "inferenceservices", "group": "serving.kserve.io", "name": "ISVC_NAME", "verb": "get"}

Currently, kube-rbac-proxy doesn't allow for "verb" at the "resourceAttribute" level. It can only be declared in the "static" section, which then also requires declaring a "user" for proper evaluation, which is not exactly the same as how it worked for oauth-proxy.

We would like to extend the configuration schema of kube-rbac-proxy's "resourceAttribute" section to have an explicit declaration of the http verb to use, instead of inheriting whatever method the incoming request is.