clear then add to mutable list.

app/src/main/java/com/sduduzog/slimlauncher/adapters/AddAppAdapter.kt

@@ -29,6 +29,7 @@ class AddAppAdapter(private val listener: OnAppClickedListener) : RecyclerView.A
     }
 
     fun setItems(apps: List<App>) {
+        this.apps.clear()
         this.apps.addAll(apps)
         notifyDataSetChanged()
     }