chore: fix useless viper dependency

Author: mmeloni

pkg/client/cache/file_cache.go

@@ -17,7 +17,6 @@ limitations under the License.
 package cache
 
 import (
-	"github.com/spf13/viper"
 	"io/ioutil"
 	"path/filepath"
 
@@ -50,7 +49,7 @@ func (w *fileCache) Get(serverUuid string) (*schema.Root, error) {
 }
 
 func (w *fileCache) Set(root *schema.Root, serverUuid string) error {
-	fn := filepath.Join(viper.GetString("dir"), string(getRootFileName([]byte(ROOT_FN), []byte(serverUuid))))
+	fn := filepath.Join(w.Dir, string(getRootFileName([]byte(ROOT_FN), []byte(serverUuid))))
 
 	raw, err := proto.Marshal(root)
 	if err != nil {