Linter to ensure go-cmp/cmp is used ONLY in tests

Signed-off-by: Davanum Srinivas <davanum@gmail.com>

Kubernetes-commit: 4e05bc20db99ff89b2d2205218d24b9935a7fdd7

pkg/admission/testing/helpers.go

@@ -21,7 +21,7 @@ import (
 	"reflect"
 	"testing"
 
-	"github.com/google/go-cmp/cmp"
+	"github.com/google/go-cmp/cmp" //nolint:depguard
 	apiequality "k8s.io/apimachinery/pkg/api/equality"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apiserver/pkg/admission"

pkg/endpoints/discovery/aggregated/fake.go

@@ -25,7 +25,7 @@ import (
 	"time"
 
 	"github.com/emicklei/go-restful/v3"
-	"github.com/google/go-cmp/cmp"
+	"github.com/google/go-cmp/cmp" //nolint:depguard
 	apidiscoveryv2 "k8s.io/api/apidiscovery/v2"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/util/wait"

pkg/storage/testing/store_tests.go

@@ -28,7 +28,7 @@ import (
 	"sync"
 	"testing"
 
-	"github.com/google/go-cmp/cmp"
+	"github.com/google/go-cmp/cmp" //nolint:depguard
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/fields"

pkg/storage/testing/utils.go

@@ -27,7 +27,7 @@ import (
 	"testing"
 	"time"
 
-	"github.com/google/go-cmp/cmp"
+	"github.com/google/go-cmp/cmp" //nolint:depguard
 	"k8s.io/apimachinery/pkg/api/meta"
 	v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/fields"

pkg/util/flowcontrol/apf_controller.go

@@ -28,7 +28,7 @@ import (
 	"sync"
 	"time"
 
-	"github.com/google/go-cmp/cmp"
+	"github.com/google/go-cmp/cmp" //nolint:depguard
 	apiequality "k8s.io/apimachinery/pkg/api/equality"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"