Remove restore queue popup when user add a new track to queue

src/audio/queue.js

@@ -91,6 +91,7 @@ class Queue {
     cache.set('volume', newValue)
   }
   append (track, index) {
+    this.previousQueue = null
     index = index || this.tracks.length
     if (index > this.tracks.length - 1) {
       // we simply push to the end