Song # isn't updated in metadata

[sharunkumar]

Describe the bug When downloading an album, the song # in that album isn't updated in the metadata of the music file

To Reproduce Steps to reproduce the behavior:

1. Download any album using musicdl

Expected behavior In metadata properties, the song # should be available. This helps in sorting in music players, file explorer, etc.

Screenshots

[insaiyancvk]

@sharunkumar That's a nice feature that can be added :)