fix static tests

Author: Nazar65

app/code/Magento/MediaGalleryUi/view/adminhtml/web/css/source/_module.less

@@ -275,7 +275,7 @@
         .media-directory-container {
             &::-webkit-scrollbar {
                 background: transparent;
-                width: 0px;
+                width: 0;
             }
             -ms-overflow-style: none;
             float: left;