* Add CLUSTER_RESOURCES_INGRESS_CLASS constant
* Collect IngressClass resources in cluster resources
* Add IngressClass analyzer API type
* Regenerate deepcopy for IngressClass type
* Update client-gen output from make generate
* Add IngressClass analyzer tests
* Implement IngressClass analyzer
* Register IngressClass analyzer in dispatcher
* Restore v1beta3 import in clientset scheme registration
The v1beta3 import was accidentally removed during client-gen
regeneration, causing a compile error since the SchemeBuilder
still references troubleshootv1beta3.AddToScheme.