[@caesarxuchao](https://github.com/caesarxuchao))

* Using kubectl gcp auth plugin with a Google Service Account to authenticate to a cluster now additionally requests a token with the  "userinfo.email" scope. This way, users can write ClusterRoleBindings/RoleBindings with the email address of the service account directly. (This is a breaking change if the numeric uniqueIDs of the Google service accounts were being used in RBAC role bindings. The behavior can be overridden by explicitly...