[xds_cluster_e2e_test] remove unnecessary check for EDS response state

test/cpp/end2end/xds/xds_cluster_end2end_test.cc

@@ -1563,8 +1563,6 @@ TEST_P(FailoverTest, MoveAllLocalitiesInCurrentPriorityToHigherPriority) {
   balancer_->ads_service()->SetEdsResource(BuildEdsResource(args));
   // When backend 2 gets traffic, we know the second update has been seen.
   WaitForBackend(DEBUG_LOCATION, 2);
-  // The xDS server got at least 1 response.
-  EXPECT_TRUE(balancer_->ads_service()->eds_response_state().has_value());
 }
 
 // This tests a bug triggered by the xds_cluster_resolver policy reusing