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

Signed-off-by: Davanum Srinivas <[email protected]>

Kubernetes-commit: 4e05bc20db99ff89b2d2205218d24b9935a7fdd7

Author: dims

config/testing/helpers.go

@@ -23,7 +23,7 @@ import (
 	"path/filepath"
 	"testing"
 
-	"github.com/google/go-cmp/cmp"
+	"github.com/google/go-cmp/cmp" //nolint:depguard
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apimachinery/pkg/runtime/serializer"

config/testing/roundtrip.go

@@ -22,7 +22,7 @@ import (
 	"path/filepath"
 	"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/apimachinery/pkg/runtime/schema"

logs/api/v1/options.go

@@ -27,7 +27,7 @@ import (
 	"sync/atomic"
 	"time"
 
-	"github.com/google/go-cmp/cmp"
+	"github.com/google/go-cmp/cmp" //nolint:depguard
 	"github.com/spf13/pflag"
 
 	"k8s.io/klog/v2"