macosx: Do not apply thumbnail for album in album table cell view if the view's represented album changed

Signed-off-by: Claudio Cambra <developer@claudiocambra.com>

modules/gui/macosx/library/audio-library/VLCLibraryAlbumTableCellView.m

@@ -328,6 +328,9 @@ const CGFloat VLCLibraryAlbumTableCellViewDefaultHeight = 168.;
     }
 
     [VLCLibraryImageCache thumbnailForLibraryItem:album withCompletion:^(NSImage * const thumbnail) {
+        if (self.representedItem.item != album) {
+            return;
+        }
         self.representedImageView.image = thumbnail;
     }];