Add more xds_lb test cases

[lidizheng]

This test suite is only fully enabled for C++ and Python at this moment: https://github.com/grpc/grpc/blob/master/tools/internal_ci/linux/grpc_xds_k8s_lb.sh

This PR enables the rest of the test suite for grpc-java:

• change_backend_service_test
• failover_test
• remove_neg_test
• round_robin_test
• affinity_test

(CC @YifeiZhuang you mentioned that the tests were failing when deployed to Kokoro, it might be caused by using the wrong GKE clusters. You were using the "basic" cluster, which don't have workload-identity turned on.)

Tested: prod:grpc/java/master/branch/xds_k8s_lb

[lidizheng]

@ejona86 PTAL. A test run passed on Kokoro.

[YifeiZhuang]

@lidizheng thanks a lot for the hint. Yes I was using GKE_CLUSTER_PSM_BASIC to run a url map test metadata filter, how is that failing because of lacking of workload-identity? Something is still wrong tho, but other url map tests are successful, e.g. grpc_xds_url_map

[lidizheng]

Yeah.... in case of a url map test failure, I think we might need to rebuild the url-map to make it right.

---
genericXdsConfigs:
- clientStatus: DOES_NOT_EXIST
  name: metadata-filter.test-metadata-filter-match-all:8848
  typeUrl: type.googleapis.com/envoy.config.listener.v3.Listener
node:
  clientFeatures:
  - envoy.lb.does_not_support_overprovisioning
  cluster: cluster
  id: projects/830293263384/networks/default-vpc/nodes/a294781a-e6eb-488a-be65-ac30f6df2f97
  locality:
    zone: us-central1-c
  metadata:
    INSTANCE_IP: 10.60.3.60
    TRAFFICDIRECTOR_GCP_PROJECT_NUMBER: '830293263384'
    TRAFFICDIRECTOR_NETWORK_NAME: default-vpc
  userAgentName: gRPC C-core linux
  userAgentVersion: C-core 23.0.0
...

[  FAILED  ] metadata_filter_test.TestMetadataFilterMatchAll.test_client_config

I can help to rebuild.