add unit tests for cmd/... in ci

Signed-off-by: lonelyCZ <531187475@qq.com>

Makefile

@@ -97,6 +97,7 @@ verify:
 .PHONY: test
 test:
 	go test --race --v ./pkg/...
+	go test --race --v ./cmd/...
 
 images: image-karmada-controller-manager image-karmada-scheduler image-karmada-webhook image-karmada-agent image-karmada-scheduler-estimator
 

cmd/agent/app/options/validation_test.go

@@ -52,7 +52,7 @@ func TestValidateKarmadaAgentConfiguration(t *testing.T) {
 				ClusterLeaseDuration:              metav1.Duration{Duration: 40 * time.Second},
 				ClusterLeaseRenewIntervalFraction: 0.25,
 			},
-			expectedErrs: field.ErrorList{field.Invalid(newPath.Child("ClusterName"), "", "clusterName cannot be empty")},
+			expectedErrs: field.ErrorList{field.Invalid(newPath.Child("ClusterName"), "", "must be not empty")},
 		},
 		"invalid ClusterStatusUpdateFrequency": {
 			opt: Options{