Clean up experimental Centralized Kubernetes Orchestrator.

RELEASE.md

@@ -21,6 +21,7 @@
 ## Major Features and Improvements
 
 *  Dropped python 3.8 support.
+*  Dropped experimental TFX Centralized Kubernetes Orchestrator
 *  Extend GetPipelineRunExecutions, GetPipelineRunArtifacts APIs to support
    filtering by execution create_time, type.
 *  ExampleValidator and DistributionValidator now support anomalies alert

build/BUILD

@@ -23,8 +23,6 @@ sh_binary(
         "//tfx/examples/custom_components/presto_example_gen/proto:presto_config_pb2.py",
         "//tfx/extensions/experimental/kfp_compatibility/proto:kfp_component_spec_pb2.py",
         "//tfx/extensions/google_cloud_big_query/experimental/elwc_example_gen/proto:elwc_config_pb2.py",
-        "//tfx/orchestration/experimental/centralized_kubernetes_orchestrator/service/proto:service_pb2.py",
-        "//tfx/orchestration/experimental/centralized_kubernetes_orchestrator/service/proto:service_pb2_grpc.py",
         "//tfx/orchestration/experimental/core:component_generated_alert_pb2.py",
         "//tfx/orchestration/kubeflow/proto:kubeflow_pb2.py",
         "//tfx/proto:bulk_inferrer_pb2.py",