  }   if len(failedGroups) == 0 {   return result, nil  }   return result, &ErrGroupDiscoveryFailed{Groups: failedGroups} }  // ServerResources returns the supported resources for all groups and versions. func (d *DiscoveryClient) ServerResources() ([]*metav0.APIResourceList, error) {  return withRetries(defaultRetries, d.server