[#609] Replace zaptest.NewLogger() with zap.L()

Semantic patch:
```
@@
@@
-import "go.uber.org/zap/zaptest"
+import "go.uber.org/zap"

-zaptest.NewLogger(t)
+zap.L()
```

Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>

pkg/local_object_storage/writecache/writecachebadger/flush_test.go

@@ -14,14 +14,14 @@ import (
 	oidtest "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id/test"
 	"github.com/dgraph-io/badger/v4"
 	"github.com/stretchr/testify/require"
-	"go.uber.org/zap/zaptest"
+	"go.uber.org/zap"
 )
 
 func TestFlush(t *testing.T) {
 	createCacheFn := func(t *testing.T, smallSize uint64, mb *meta.DB, bs writecache.MainStorage, opts ...Option) writecache.Cache {
 		return New(
 			append([]Option{
-				WithLogger(&logger.Logger{Logger: zaptest.NewLogger(t)}),
+				WithLogger(&logger.Logger{Logger: zap.L()}),
 				WithPath(filepath.Join(t.TempDir(), "writecache")),
 				WithMetabase(mb),
 				WithBlobstor(bs),