Fix error in serialization with albums

mopidy_webhooks/frontend.py

@@ -32,7 +32,7 @@ class WebhooksFrontend(pykka.ThreadingActor, CoreListener):
         return {
             "name": track.name,
             "artist": artists,
-            "album": track.album,
+            "album": track.album.name,
             "track_number": track.track_no,
             "run_time_ticks": track.length,
             "run_time": str(duration),