containers: Update OAuthClient for OpenShift 4.x
containers: Update OAuthClient for OpenShift 4.x

This change updates the OAuthClient to:

1. Use the groupified apiVersion
2. Drop the allowAnyScope field (it was removed long ago)
3. Set grantMethod to auto as that is required in OpenShift 4.x

Closes #11406
deryni/cockpit,martinpitt/cockpit,mvollmer/cockpit,garrett/cockpit,moraleslazaro/cockpit,cockpit-project/cockpit,deryni/cockpit,mvollmer/cockpit,deryni/cockpit,cockpituous/cockpit,cockpituous/cockpit,cockpituous/cockpit,martinpitt/cockpit,martinpitt/cockpit,cockpituous/cockpit,moraleslazaro/cockpit,cockpituous/cockpit,martinpitt/cockpit,cockpit-project/cockpit,garrett/cockpit,moraleslazaro/cockpit,moraleslazaro/cockpit,garrett/cockpit,mvollmer/cockpit,moraleslazaro/cockpit,mvollmer/cockpit,cockpituous/cockpit,moraleslazaro/cockpit,moraleslazaro/cockpit,mvollmer/cockpit,cockpit-project/cockpit,garrett/cockpit,martinpitt/cockpit,deryni/cockpit,deryni/cockpit,garrett/cockpit,deryni/cockpit,cockpit-project/cockpit,deryni/cockpit,cockpit-project/cockpit